The Local

A Tennessee man who knew the Great Smoky Mountains National Park like the back of his hand disappears into the forestland that surrounds his 100-acre property. The only clue left behind is an idle ATV, indicating he stumbled upon something sinister and never saw the light of day again.

The Episode

Hi park enthusiasts.

I’m your host Delia D’Ambra…

The story I’m going to tell you about today is a bizarre one…that to this day is still unsolved.

It takes place in Great Smoky Mountains National Park…the most visited national park in America according to the National Park Service.

This park takes up more than 520-thousand acres and is divided almost evenly between Tennessee and my home state of North Carolina.

There 850 miles of backcountry trails, many of which twist and turn on themselves or intersect with private properties.

And it’s on one of these trails in the summer of 2008 that 51-year-old Mike Hearon disappeared…leaving behind a mountain of mystery as big as the Great Smokys themselves.

To help me tell this story, I enlisted the help of one of Mike’s sons, Matt Hearon.

Matt and his brother Andy have been looking for their father, who vanished in the woods along the park’s boundary 13 years ago…and the men are certain, he was murdered.

This is Park Predators.

*Cell phone ringing*

Around 9:30 in the morning on Saturday, August 23rd, 2008 26-year-old Andy Hearon picked up his phone and heard the cheerful voice of his father, Mike Hearon, on the other end.

Mike was calling Andy to let his son know that he was leaving his condo in the nearby town of Maryville, Tennessee and coming over to Andy’s house to pick up a lawn mower and trailer.

Mike told his son that he wanted to take the mower about 30 minutes away to the family’s 100-acre farm in Happy Valley.

Right before calling Andy, Mike said he’d tried to reach his other son, 25-year-old Matt Hearon and tell him the same thing, but Matt hadn’t answered, so he left a voicemail.

Matt Hearon: He left me a message on my cell phone, just saying he was going up to the Valley for the weekend. There was nothing strange about the message or anything like that. He went up on the weekends, to Happy Valley, where his farm was about every weekend.

Delia D’Ambra: Andy told his dad that using the mower for the weekend was fine. The piece of equipment was something Mike and his sons shared and swapped back and forth. All three of the men worked as contractors for Mike’s construction company in Maryville and would often use the mower to maintain the land around houses or buildings they’d built.

During the call, Mike told Andy that he’d been wanting to get out to the farm and mow down some tall grass on a neighboring 40-acre property owned by some missionaries that were out of town. It was summer after all and grass in the unattended field was really needing to be trimmed.

Andy wasn’t at home when his dad called him but while they were on the phone he told him he was on his way back and could help Mike put the mower on the trailer.

He told his dad that if he didn’t want to wait for him, he could go ahead and transport it by himself.

Andy and Mike lived about a half-hour apart so Andy figured he’d either see his dad loading the mower and help him… or pass him on the drive.

And that’s exactly what happened. Andy told The Daily Times that as he pulled down his road his father passed him driving in the direction of the family’s farm.

Matt Hearon: He actually saw dad going down Gateway Road with his trailer and the mower loaded up, and he was headed like towards the parkway, to head up over the mountain.

Delia D’Ambra: Andy said he noticed that Mike had the mower on a trailer and everything seemed completely normal. The two didn’t talk after that. Andy had no idea THAT was the last time he’d ever see his father.

*Truck pulling into gravel driveway*

A few hours later, around 11:00am, Mike’s neighbors who lived next to his property— saw him pull into the driveway of his property near the end of Bell Branch Road hauling a piece of equipment on a trailer.

Mike’s house was towards the dead end of Bell Branch Road, so he passed a lot of the other farm estates on the way to his property.

According to The Daily Times, 30 minutes later two other neighbors on the dead-end road saw Mike emerge from his property riding on a four-wheeler. Mike waved at some of them as he zoomed toward the woods.

The rest of Saturday passed and Andy and his brother Matt didn’t think twice about not hearing from their father. It wasn’t like they spoke with him every day. Like I said, Mike did employ both of his adult sons as contractors at his construction company in Maryville, but it was the weekend and the brothers and their father were living their separate lives.

Andy and Matt just assumed Mike would call and return the mower and trailer to one of them whenever he was done with it or all of them would touch base at work on Monday.

So, the brothers were surprised when on Sunday, August 24th around 2:00 o’clock in the afternoon their grandmother called.

Matt Hearon: I remember my grandmother, his mother, had called and asked if I’d talked to him. She hadn’t talked to him or anything. She hadn’t been able to get a hold of him.

Delia D’Ambra: Mike’s mother, Alma, was upset. She asked the boys if they’d heard from their dad and they both told her no. She explained to them that she hadn’t heard from Mike all weekend which was unusual.

She told Matt and Andy that mid-morning on Sunday, she and Mike’s dad had walked down about 5 minutes from their house on Happy Valley Road to Mike’s house on Bell Branch Road and knocked on Mike’s door, but no one answered. The couple hadn’t gone inside but they noticed Mike’s truck was sitting in the driveway with a mower and trailer attached to it.

Andy and Matt weren’t really alarmed by the fact that their dad hadn’t answered the door or unhitched the trailer. They knew he would often work on projects outside on the farm, or be taking care of his 40 head of cattle and dozens of chickens. They also knew that Happy Valley wasn’t friendly for cell phone use.

Matt Hearon: There is no cell phone service in Happy Valley. I don’t know if you’re familiar with that or not. There’s no cell phone service. Basically, there’s a landline he would use. But if he’s out on the tractor, or out hunting, or doing stuff with the cattle, or working the fences or something like that, he wouldn’t have been able to get a hold of. It really didn’t raise any red flags to me on Sunday, when my grandmother called and asked if I’d talked to him.

Delia D’Ambra: The men told their grandmother that Mike was probably just busy on the farm and once he was back near a phone, he would call her.

The brothers knew that the farm property itself was where Mike had been raised. The surrounding woods were where he’d grown up. Mike had told his two sons stories of how as a boy he’d adventured and enjoyed spending time in the forest.

At one point Mike had even worked as a ranger for the park service trimming trails.

Matt Hearon: He knew that area like the back of his hand. You could send him out there and drop him somewhere, probably anywhere around that area in the pitch black, in the dark, and he could tell you exactly what’s what and what landmarks are here and there. He knew the area very well.

Delia D’Ambra: According to Matt and news reports, on Monday, August 25th, Alma called Matt and Andy again. This time she was in a real panic. She told them that she had still not heard from Mike and she felt something was very wrong.

It was around 8:30 or nine o’clock in the morning and Andy and Matt realized after speaking with her this second time that they needed to check on their dad. So, Matt drove to Mike’s condo in Maryville to scope it out.

The condo was where Mike usually stayed on weeknights or when he wasn’t at the farm.

When Matt arrived he saw nothing out of the ordinary. Mike’s bed was made and all of the lights were off. It looked like he’d left in a normal manner just like he always did.

Matt Hearon: Nothing was out of place. He had a Mercedes, a little convertible car, and a Harley. They were both in the garage. So we knew he was in his truck, obviously, still.

Delia D’Ambra: The only vehicle missing was Mike’s pickup truck, which Matt knew from talking with his grandmother, was at the farm.

After checking on the condo Matt met up with Andy and the two headed to the farm. Mike’s mother had gone back to the farmhouse for a second time to check for signs of him. When she got there, she called Andy and Matt to tell them that a four-wheeler was sitting in the front yard and Mike’s truck was still parked by the house with the lawn mower and trailer attached to the back of it.

Matt Hearon: Said his truck was still parked there with the trailer on, and the lawnmower on the back. The windows were rolled down. It looked like he just kind of left it there temporarily. It was just kind of not in the state you would leave something, if you were going to park it for a long time or anything like that.

Delia D’Ambra: Andy and Matt quickly made their way over to the farm and found Mike’s truck there just as their grandmother had described it. It was parked with the windows down and the doors unlocked.

Inside they found their dad’s keys, ID, some cash and his cell phone laying on the seat.

Something else strange was the way the truck was parked. It wasn’t how Andy and Matt knew Mike to normally park it.

The brothers knew that Mike had a regular habit of letting a school bus from the area park on the property on weekday mornings. In order for that bus to have parked in its usual spot come Monday morning, Mike would have had to position his truck in a specific way to let the bus through. The way the brothers found their dad’s truck though told them that he hadn’t moved it for the bus.

They noticed a four-wheeler in the yard, which was the one their grandmother Alma had told them about on the phone. The brothers inspected it but quickly realized it was old…their dad had recently purchased a new one and THAT one was the one missing.

For Matt, the missing ATV really concerned him. It meant that his dad was out there and at one point had a mode of transportation but for some reason hadn’t come back with it, which probably meant he was injured badly.

Matt felt that worse case, Mike had gotten into an accident on the four-wheeler and was perhaps injured.

Around noon time on Monday, the men had alerted some close family members that Mike was missing on his property and then called their mother. Their mom and Mike had been divorced for six or seven years at this point but she still lived in Maryville. She drove to Happy Valley to help her sons try to locate her ex-husband.

Jerry Hearon, Mike’s brother, learned about the search for Mike while he was at work. Jerry’s wife had called him to explain what was going on.

Jerry immediately thought to himself, the same thing Matt had, which was that maybe Mike had fallen or wrecked a four-wheeler in the woods or been injured. He remembered that his brother had mildly high blood pressure but other than that Jerry knew Mike was healthy.

Back at the farm, Andy and Matt worked together to repair a flat tire on the old ATV sitting in Mike’s front yard and then they began searching the 100-acre farm themselves.

Matt Hearon: Me and Andy searched. We just took our trucks at first and rode the main trails on the farm and didn’t see anything.

We were combing all the 140 acres that we own…and there’s actually a property that dad was mowing for some missionaries that were in the Philippines. He’d sold some property a long time ago. He was going to go up there and mow it for hay. He already said he was going to do that. So, we went. We drove out there and looked and didn’t see anything.I mean it was probably, I would think, two or three hours, maybe more than that. We looked everywhere we thought to look.

*Rain & four wheeler driving*

Delia D’Ambra: The brothers rode on dozens of trails and even went to nearby campgrounds inside Great Smoky Mountain National Park to try and find Mike.

After several hours of searching in the forest and not finding a single trace of their father, Matt and Andy started to think the worst.

By four o’clock, the brothers decided to call the police.

Because the Hearon farm is so close to the national park but not technically inside of it, Matt was first connected with dispatchers with the National Park Service…but eventually was transferred to Blount County Sheriff’s office.

Around six o’clock Monday night, deputies began arriving at the family farm…but they hit a roadblock right away.

Matt Hearon: I think the Sheriff’s Department members showed up just a little bit before dark. It was probably about 30 minutes to an hour into the search, that’s when it started raining. It rained for, I think, two or three days straight.

Delia D’Ambra: An officer with a tracking dog tried to pick up Mike’s scent around the farmhouse and his empty pickup truck but couldn’t. The rain and bad weather made it difficult to accomplish anything.

According to the Knoxville News Sentinel, the next morning the Blount County Sheriff’s Office launched a formal search for Mike.

They asked the public and media for help and to be on the lookout for the missing four-wheeler and any sign of Mike..

According to the witnesses on Bell Branch Road who saw Mike on Saturday, the clothing he was last seen wearing was a faded red t-shirt, khaki cargo shorts and Teva sandals.

Some good information that would help people identify him was that he had a distinct surgical scar on the back of one of his knees…a snake bite scar on one of his feet and a tattoo on his lower back.

Some of Mike’s other identifying features were that previously in his life he’d had had his appendix removed, so he would have a scar on his abdomen.

He had also had caps put on his teeth. Which we all know, teeth are some of the best identifying markers of a person if they’re found dead and there isn’t much left to I-D them.

But despite all of the helpful information about Mike, no one came forward right away to say that they’d seen him.

It was literally like he disappeared into thin air.

Blount County Sheriff’s Office headed up the investigation.

The lead sergeant noticed two big problems right away….One, the authorities were late to the party because Mike’s family had inadvertently delayed officially reporting him missing.

And two, all of the wind and rain that had started up on Sunday worked against deputies. Any clues or tracks that may have been left in the woods on Saturday when Mike was last seen…could have washed away.

At daybreak on Tuesday, August 26th, Blount County sheriff’s deputies and search and rescue crews from the National Park Service and area fire department resumed their search for Mike and began meticulously walking through the woods on and around his property.

Mike’s sons Matt and Andrew joined authorities, still desperate to find any trace of their missing father.

One of Mike’s next-door neighbors on Bell Branch Road, a man in his 80’s named Grady Whitehead volunteered to lead some of the search parties. Grady had been one of the people to briefly see Mike the Saturday he disappeared. Grady remembered Mike riding his ATV past his house and waving.

Grady’s own son, also named Mike, had grown up with Mike Hearon. The two families were very close. Grady had actually been a park ranger in Great Smoky Mountains National Park from 1955 until 1988. So, he knew the land well and had a reputation as an expert tracker.

Grady’s wife told the Knoxville News Sentinel that Grady was so passionate about finding Mike that he every day searches were underway he was quote — “the first one on the search and the last one off.”–en quote.

Grady used all of his tracking skills to help point authorities to possible signs of Mike but nothing panned out. Grady told the paper that the vegetation in Happy Vale would have indicators like bent weeds or bushes if someone had walked through an area or fallen and then tried to find help.

*Helicopter and dogs barking*

The massive search for Mike covered close to 500 acres and included helicopters, dogs, drones and people on horseback. The sheriff’s office also brought in divers to drag two ponds on Mike’s property.

By mid-afternoon on Tuesday, August 26th, authorities FINALLY got the break they needed.

Deputies had made a huge discovery…one that would change everything about this investigation and would send rumors flying in Happy Valley…

Around noontime on Tuesday, August 26th, Blount County Sheriff’s deputies found Mike Hearon’s ATV. Mike though was still unaccounted for.

According to The Daily Times, one of Mike’s friends had found the ATV while randomly checking an area off of Happy Valley Loop, a road that leads to Bell Branch Road.

The ATV was abandoned about a mile away from Mike’s farmhouse. It was parked in thick woods near an abandoned cabin.

*Police radio chatter/static*

When the ATV was actually located, Andy and Matt were searching in different sections of woods nearby and heard the radio chatter come through the walkie-talkies.

Matt Hearon: When they said they found it, I remember my heart sank, because I just didn’t know. I knew we’d find it. Wherever the 4-wheeler was, I just envisioned he had flipped it, or done something, or killed himself, or hurt himself. Because I just knew that’s what was going to happen.

Delia D’Ambra: But when Matt and his brother got to the spot, that sure feeling that his dad had wrecked the four-wheeler and would be nearby, quickly went away.

The brothers saw the ATV and knew right away that it was the one that belonged to their dad…but where it was found was NOT a location Mike should have been. They had no idea why the four-wheeler would be where it was.

Matt told me that was the moment he felt in his heart whatever had happened to his dad was not an accident.

Matt Hearon: Once they took me where the 4-Wheeler was found, I knew right away, I thought, “Yeah. There was foul play involved.” Because it didn’t make any sense where and how the 4-wheeler was left. That he would have put it there or that he… Something happened that wasn’t right. It’s how the 4-wheeler was there. It wasn’t on his property. It was in between his property and the property that I had mentioned that he was mowing for hay for the missionaries, which was probably about a mile and a half, maybe a mile up the road. It was kind of in between those properties.

Delia D’Ambra: So, it wasn’t technically in the National Park?

Matt Hearon: No. It wasn’t in the National Park.

Delia D’Ambra: But close area?

Matt Hearon: Right. Yeah. Yeah. It was a three-minute walk to the National Park.

Delia D’Ambra: Matt described the position of the four-wheeler as sort of stashed up a steep hill in a strange way. Almost like someone had jumped off of it in a hurry or it had been ditched there last minute.

When Matt and deputies with the Blount County Sheriff’s office looked closer at the dashboard, they saw that the four-wheeler was left in high gear with the ignition switch in the “on” position but the kill switch off.

Nothing else about the four-wheeler indicated it had been damaged or wrecked in any way. It was just sitting there. Deputies tried to lift fingerprints from the handlebars but the rain and bad weather the previous days washed it pretty good.

Matt and Andy told the sergeant that their dad would never have left an ATV with an ignition switch on. It would drain the power and the last thing their dad would have wanted while deep in the woods would be to run out of juice and be stranded.

Matt Hearon: The ignition key was on but somebody hit the kill switch to shut it off. And where it was found it was on a hill and it was in high gear. I think he said, third or fourth gear, and it was kind of just stashed over in some brush. It wasn’t like somebody had made a decision to park it in a good spot. It looked like it had been driven in a hurry and somebody had just stashed it.

You know, when it was found like that, my first thought was that he did not put the 4-wheeler there.

Delia D’Ambra: The next morning, Wednesday, August 27th, deputies and more than 50 community volunteers fanned out around where the four-wheeler was found to search for clues.

This area is remote and has thick vegetation. It actually bleeds over into the boundary of the national park…so we’re talking dense woods and uninhabited forest that stretch for acres and acres.

This part of the valley is so remote that the sheriff’s office had to set up a mobile cell tower at the investigation’s command center in order for people to get enough cell service to communicate.

Deputies used a scent tracking dog to attempt to pick up Mike’s trail …starting at the abandoned four- wheeler and moving outward, but it led nowhere.

According to the Daily Times, that same day a park ranger-led a group of volunteers to search around a cave that Mike’s family said he knew about and would sometimes go to, but they found nothing there either.

The Blount County Sheriff’s office officially called off the search for Mike on Friday, August 29th, 2008.

In January 2009, some emergency workers resumed searching the backcountry around Mike’s land. They battled cold weather and snow flurries as they worked..but still made little progress.

The sheriff’s office prompted this renewed search for Mike so many months after his disappearance because the fall season had caused a lot of the leaves and foliage in the woods to clear away, which made it easier for searchers to cover more ground.

According to a report by Robert Wilson for the Knoxville News Sentinel searchers in 2009 found an article of clothing near the area where Mike’s ATV was located but it didn’t come back as a match for him.

They also found some bones … and that really got Mike’s family and all of Happy Valley’s attention…

The bones that searchers found in 2009 were located in a fire pit not far from where Mike’s abandoned ATV had been found months earlier.

The development gave the Heron family a lot of hope and at the same time despair. If the bones were Mike’s that meant he was for sure dead.

…but when the lab test results came in… they showed the bones were from a cow. Not human and not Mike.

And that is where leads in this case just completely dry up.

For 13 years authorities have asked people for help and even offered a $15,000 reward, but still nothing has materialized that points to what happened to Mike.

Matt and Andy have had to hold out hope that someone will stumble across a clue in the woods in order to kickstart the case again.

Matt Hearon: I just every year, when hunting season comes around, I just pray that somebody finds… I think our best chances are the hunter or something that runs up on remains of some sort, and then we get some kind of, something going off of that.

Delia D’Ambra: Now, I don’t like to spiral too much on theories and what-ifs …but several people who have spoken publicly about this case and many others who have posted about the case on forums and blogs over the years have brought up some interesting theories.

One is that maybe Mike was depressed and just walked away from his life. Or that his construction business wasn’t as successful as it appeared as the American housing market crash of 2008 consumed the building industry.

Law enforcement investigators had to consider this scenario too in the beginning. I mean, Mike was a grown man and could make himself go missing if he wanted to…but something about that theory just doesn’t sit right with Mike’s family.

Matt is certain that his father did NOT willingly disappear.

Matt Hearon: We definitely don’t think that happened. He was too close to his mom. Me and my brother had just gotten married. There’s no reason he would have gotten up and walked. You know? That’s one thing my brother and I can clear, that he didn’t just make himself disappear.

Delia D’Ambra: Matt says his dad didn’t suffer from depression, the Hearon building business never was in financial trouble and his Mike didn’t have any enemies.

Matt Hearon: We had a really good 2007. We had a lot of specs that were doing, and we kind of cleaned out a lot of the inventory and we weren’t really in a bind when the market crashed, I guess at the end of ’08. We were in pretty good shape, as far as the business goes.

We can’t think of anybody, like I said that was an… Me and Andy cannot think of somebody that would want to do something like this to him. We don’t think that he was caught up in something that was… That somebody would have planned this ambush or something like that. I don’t know of anybody that would have known that he was going to be up there, but me and my brother.

Delia D’Ambra: Matt and Andy believe in their hearts that someone who shouldn’t have been in the woods or on the neighboring 40-acre property Mike was planning to mow did something to him.

Matt believes his dad is dead but isn’t sure where his body is or how a killer could have even gotten it out of the area undetected.

Matt Hearon: I think that he was going to check on that property and somebody…This property he was checking on, it was on 40 acres. This was another property like my father’s, but really no one has any visual sight of this house. The equipment barn at the bottom of the hill, and there’s a pond and stuff like that. We just feel that he was going out there to check on it and somebody was there that shouldn’t have been there.

Somebody could have been breaking in. Something happened there and then whatever happened, they got rid of… They stashed the 4-wheeler on that road or did something. We just have a hard time picking an enemy that would have done something like this.

Delia D’Ambra: The theory that Mike may have stumbled upon someone or a group of people doing something illegal in the woods or on that neighboring property and they had to silence him seems like a possible scenario to me.

Especially when I read a few posts on social media from people who claimed they grew up with Mike. These posters said that in 2008, homeowners with property that butted up to Great Smoky Mountains National Park, just like Mike’s, had indicated there had been instances of people using the cover of the forest to grow marijuana in Happy Valley.

I couldn’t find any confirmation of this from the Blount County Sheriff’s Office directly, but this theory got so much attention in Happy Valley that people just began to think it was the only logical explanation.

Matt thinks that theory does make sense. He’s sure that if his father came across people doing something illegal just a mile outside of his property, Mike would have confronted them.

Matt says his dad was not one to let criminal behavior or wrong things go unreported. Mike was a very protective and responsible person who would have intervened if he saw something illegal or wrong going on.

Other theories that swirled around have suggested that maybe Mike himself was using the woods near his property to do something illegal…but I couldn’t find ANY information from law enforcement or official sources supporting this theory.

There’s just not enough out there in this case to say one way or the other and Mike’s family has never indicated they knew he was up to anything nefarious or illegal.

If Mike did for some reason walk away from his life to start a new one, why has he NEVER contacted his sons or family members? No financial activity has ever been seen on his bank accounts either which to me indicates that he is not alive and carrying on with another life somewhere.

Another theory many people have brought up is that perhaps Mike just lost control of his four-wheeler. Maybe he was just going too fast, hit a bump or tree root and was ejected really far away from the ATV.

From what I’ve read online, the main reason a lot of people speculate this theory is the way that the four- wheeler was positioned when it was found.

A lot of people familiar with these kinds of off-road vehicles wrote that the ignition switch being left in the “on” position but the kill switch off…could indicate that Mike fell off the four-wheeler sometime during his ride…then the vehicle kept going on its own until it ran out of power and ended up stopped in a weird way, up the hill near the abandoned cabin.

And I definitely entertained this idea while researching this case… but I keep coming back to the point that Matt made which is that Mike’s body has NEVER been found. Not even as much as a shoe, a piece of clothing or a bone.

I feel like if the scenario really was that Mike just fell off the four-wheeler somewhere and tumbled down a hill or gully or something…SOME trace of him would have been found BY NOW. Like, even if animals had scavenged his remains…there would be something, other than the ATV, to indicate he was in that area.

The woods all around where deputies found the ATV was searched thoroughly and authorities have never found a sign of Mike. That just leads me to believe that he isn’t still there and was never there for long.

One year after Mike disappeared, his friends and family gathered together to remember him. They essentially held a celebration of life service.

Matt and Andy began organizing an annual hike called “Hike for Mike” along the trails outside their dad’s property in Happy Valley. That event continued for several years but eventually ended.

Mike’s sons remember him as ‘very animated’ and that he had a loud laugh and big smile.

Most of his friends described him to reporters as being a social guy who got along well with everyone and really enjoyed his life. Matt told The Daily Times that his father worked hard to build his company and enjoyed going on vacations and riding 4-wheelers and motorcycles.

As Matt and Andy have grown older they’ve become fathers themselves.

Matt Hearon: I’ve got a 6 and 8-year-old, and my brother has a 7 and 9-year-old. For them, not… For the whole family not to really know what happened, it’s kind of a cloud that.

We’re just not really ready to go through the full in-depth of what happened. They just know that Papa Mike is passed away, is what we’ve told them. We haven’t really said anything other than that.

We know whatever has happened to him is not good. We know that he’s not alive. We just want to know what happened.

Delia D’Ambra: And that’s what I’m going to ask of you…if you are listening and have any information regarding Mike Hearon’s disappearance please contact the Blount County Sheriff’s Office Crime Hotline at (865) 273- 5200.

Park Predators is an Audiochuck Original Podcast.

Research and writing by Delia D’Ambra with writing assistance from executive producer Ashley Flowers. Sound design by David Flowers with production assistance from Alyssa Gosztola.

You can find all of the source material for this episode on our website,

So what do you think, Chuck? Do you approve? *howl