At least once a week for the past 17 months, L.C. Davis places a call to the detective assigned to his younger brother's murder investigation.

Until Davis knows what happened to his brother, Ryan Cobbins, on Oct. 24, 2013, in Kansas City, Missouri -- and who was responsible -- he'll continue to make that call, asking for updates.

In the meantime, his mind can't help but fill in the blanks itself. Occasionally, it still keeps him up at night.

"I've played out so many scenarios in my head," Davis told ESPN.com. "That's why I call the detective once a week, to see if he can tell me anything new."

Davis, 34, will be Hideo Tokoro in a bantamweight fight at Bellator 135 on Friday in Thackerville, Oklahoma.

It's a meaningful fight for Davis, who is 2-0 under the Bellator MMA banner and seeking bouts against the promotion's top talent in Joe Warren, Eduardo Dantas, Marcos Galvao and Mike Richman.

A nine-year veteran, Davis (22-6) is still looking for that "breakthrough" moment. After a three-fight skid from 2010 to 2012 as a featherweight, he has revitalized his career by dropping to the 135-pound weight class. He is 6-1 since making the change.

Fighting out of Kansas City, Davis has succeeded in the cage despite facing a personal tragedy outside of it.

Cobbins was 25 at the time of his disappearance. His body was found two months later in an abandoned house a few blocks from where he was last seen.

"He was tied up and executed, pretty much," Davis said. "He was found in the bathtub, with zip ties around his ankles and feet."

In the past few months, Davis says, the investigation has turned into a federal case. He's not privy to many details, but says the current suspects involved were apparently linked to several other active criminal investigations.

Cobbins was last seen at a barber shop in Kansas City, his lifelong home. Detectives have told Davis that his brother was abducted in broad daylight, which Davis has always found hard to accept.

His brother was a 6-foot, 230-pound former collegiate athlete. Subduing him against his will would have been a challenge, Davis says.

At one point last year, Davis says, he became a little obsessed with finding out the details of his brother's disappearance himself.

Despite his best efforts, many questions remain.

"I've been to the place where he was last seen and I've been to where his body was found," Davis said. "I've asked around. I've gotten in touch with people I probably shouldn't have. One of the prime suspects I was really digging into, detectives actually have him in custody now.

"I heard a lot of rumors, things in the street. I heard when he was first kidnapped, people were asking for ransom. I even heard some of Ryan's friends paid whoever it was that was asking for it, but now they're not speaking up. I don't know, man. I've never known what went on."

Any older brother would likely react to his sibling's disappearance as Davis did, but he says he has always felt a heightened sense of responsibility for Cobbins.

Growing up, the two moved throughout the Kansas City area as their single mother looked for work. Davis guesses he was never in the same school system for more than one year, until his freshman year of high school. With their mother constantly gone working, Davis says Cobbins was like "his son," rather than his brother. He cooked meals for him and got him ready for school.

When Davis reached his freshman year of high school, however, he decided to move in with his father, who could offer a far more stable environment in Kansas.

Davis agonized over whether to leave Cobbins alone in that migrant lifestyle, but ultimately had to make a decision to improve his own life.

"We were really close and that was a hard thing for me, to leave him," Davis said. "He was actually the reason I didn't go to live with my dad sooner. I had to do what was best for me at that time, though."

Davis went on to wrestle in college, which would eventually lead him to mixed martial arts. Cobbins also wrestled at the collegiate level at the University of Central Missouri, Davis said, but dropped out after one year.

The two spoke once or twice a month, but didn't see each other often. Davis was committed to his MMA career, while Cobbins started to fall in hard with "the wrong crowd."

In 2008, Davis received a call from his brother in the middle of the night, saying he'd been in a shootout and had been shot in the head. Davis didn't believe him at first, but later found out a bullet had grazed Cobbins' head and even entered part of his skull. He remembers urging Cobbins to see the incident as a wake-up call.

Davis moved back to Kansas City in 2010 and rekindled his face-to-face relationship with Cobbins. The two sometimes worked out together at the gym. Cobbins joked about how much tougher his older brother was than him, despite the fact he outweighed Davis by more than 50 pounds.

With a win against Tokoro (32-27-2) on Friday, Davis is hopeful higher profile fights are in his near future.

He'd love to call and text Cobbins to talk about his career -- Cobbins, even during troubled times, was a big fan of what Davis accomplished in the cage.

Davis, who was once considered a top featherweight when he fought for the WEC, says he's fighting for himself, his brother and his two nieces, who now live in Dallas.

He'll continue to make his weekly call to the detective to ask questions about the case, but he also tries to take time to focus on his brother's memory -- and not only his disappearance.

"I saved our last text conversation on my phone," Davis said. "I will look at it from time to time. He asked me what time my class at the gym was starting that day. He only did it for exercise but he was a super-good athlete. I think he would have been good at fighting, too."