Dependable, organized and on time.

It’s how friends and family would describe Derek Lueking. So it was a surprise the day he didn't show up for work.

“When I left, his alarm was going off, and went off the entire time I was going to work, and I thought maybe he had left and forgot to hit his alarm,” described Ryan Moulden.

Derek Lueking was declared missing on March 17, 2012. Courtesy Lueking family

He didn’t know it at the time that the familiar sound of the alarm meant something was off.

“When he didn't show up for work it was super unusual and that was our first hint that something was not normal,” said Moulden.

Moulden's roommate was missing.

Who was Derek Lueking?

“Derek was quiet, but he wasn't meek,” Moulden said. “He had a servant heart, went overseas, and helped the poor and those who needed a voice.”

After graduating from Johnson University, the pair became roommates. Lueking worked as an orderly at Peninsula Behavioral Health. When a mutual friend alerted Moulden that Lueking didn’t show up for work that morning in March 2012, he called Derek’s family.

“I know when people call parents with concerns about children it is not good,” said Tim Lueking, Derek’s father in a phone interview.

The search for Derek

The Luekings traveled from their home in Virginia through the night to Tennessee.

“I never thought we would lose Derek, it would just be to find him,” Tim Lueking said.

On Derek’s computer, they found he had searched the Great Smoky Mountains and booked a micro-hotel in Cherokee, North Carolina.

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At the hotel, they saw video footage of Derek checking in, and police helped them access his room.

“It was so strange, there was a Bible on the bed and a bottle of liquor on the floor just like he was thinking,” Tim Lueking said.

The family drove to nearby trails and found Derek's white Ford Escape near Newfound Gap.

Derek Lueking was 24 when he disappeared. Courtesy Lueking Family

“I thought he went for a hike or walk, he'll be back,” Tim Lueking said.

Derek was declared missing on March 17, 2012. But a note found inside his vehicle told them otherwise.

"It said, 'Don't come find me,'" Tim Lueking said.

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Derek’s wallet, keys and hiking equipment were also inside the vehicle. Trail runners and rescue crews searched the mountain for days with no luck.

“The rangers asked me if Derek would take his life, and I said up until now I would have said absolutely not, but there in the circumstances, there was that possibility,” Tim Lueking said.

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What happened?

Earlier that year, Tim Lueking had noticed a change in his son.

“He started drinking a little bit and smoking cigarettes, which was highly unusual for him,” Lueking said. “He wasn't happy with his job, where his life was going."

He assumed Derek was dealing with the post-graduation stress and transition to adulthood.

“His family and I and many others have tried to figure out what was his intentions, his motives, what happened, each time we have one, something pokes a hole in it,” Moulden, Derek's roommate, said.

Almost 6 years later, still no answers

Today Derek's mother runs a Facebook page, keeping his story alive.

“It’s tough to relive those things every day, looking at pictures,” described Lueking. “We are still hoping to find out what happened to him. It’s a difficult thing to not have any closure on the situation.”

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They cling to their faith, praying one day an answer will come.

“I’m not blind to the fact that he could have died, someone could have taken his life, it could have been an accident, but we all hope that we don't know something and he is out there,” Moulden said.

If you know anything about Derek’s case, you can share the information with the National Park Service at 865-436-1230.

Any tips can help bring his family the answers they need.