Las Vegas: A city where dreams can be made and lost in a matter of seconds. A city where two bodybuilding phenoms would grab headlines for all the wrong reasons.

Craig Titus and Kelly Ryan were two stars who sparkled on the Las Vegas Strip. But a dark secret behind their picture-perfect marriage of muscle, money and health would bring their empire tumbling down.

A fireball cracks the pitch-black night in the desert just outside of Las Vegas. A Jaguar automobile is torched. The license plate is registered to famous bodybuilder Kelly Ryan. And there's a charred body in the trunk.

Kelly Ryan is known to the fitness world as "Flyin' Ryan," at one time holding the Ms. Fitness America title. Her dazzling routines wowed crowds and landed endorsement deals around the world. Ryan won Ms. Fitness Olympia, Fitness International, and nearly a dozen other competitive titles.

Denise Dinger, also a professional bodybuilder and a friend of Kelly Ryan's, says she was the "It" girl. They spent countless hours in the gym building muscle and dreams of marketing Dinger's health bar company with Kelly's famous face.

Kelly's strength and body control gave her the ability to soar heights far greater than her 5-foot-3inch frame. Her magic on the mat also caught the eye of the famed "Bad Boy of Bodybuilding," Craig Titus. Titus held his own catalog of titles, including IronMan and Mr. Olympia.

As the couple's passion for each other grew, so did their careers, gracing several magazine covers and fitness expositions together. From the outside it looked like they were the perfect power couple, but behind the bleached-white smiles there were dark secrets that could affect their carefully sculpted reputations. Did those secrets all blow up in their faces that dark night in the middle of the desert?

When police showed up at the couple's Las Vegas home, they were shocked. Kelly Ryan opens the door, alive and well. In fact, she doesn't even seem bothered when cops tell her about her torched Jaguar with a body in the back. Instead she's fuming about an argument she and Craig had with their live-in assistant, Melissa James. They tell police Melissa's been stealing from them, and now she's mysteriously disappeared.

Melissa James is professional dancer and a trained ballet, hip-hop and jazz instructor who grew up on a stage. She opened her own dance studio in Florida when she was just 19 years old.

Melissa's mother, Maura James, says the light in her bright blue-eyed girl dimmed after a bad business deal put her dance studio in jeopardy. That's when she met Craig Titus at a fitness competition. There was an instant connection, and he persuaded her to move to Las Vegas.

Melissa hoped to hit the jackpot in Vegas. She thought working with the "super couple" of bodybuilding could put her on the fast track to fame and fortune -- at least help her earn enough money to get her dance studio back. Melissa was all in, and actually moved in with Craig and Kelly, her new best friends.

But the high life was short-lived for Melissa, she told her mom: Promises were broken, she was never paid, and Craig and Kelly were often in a drug-fueled state of paranoia.

Clark County Assistant District Attorney Robert Daskas says that according to Craig, he and Melissa were more than just friends. They had a brief romantic relationship at some point. When Kelly found out, it was an image she couldn't shake.

Maura says after living just four months with the couple, her daughter was ready to pack up and go.

Craig booked Melissa a flight home for Christmas. She told her mom she was done with Vegas and was leaving Sin City for good. Hours before her flight, tensions reached a boiling point. Las Vegas Police Detective Dean O'Kelley says Melissa flexed her muscle, threatening to expose the power couple.

Melissa's mom, Maura James, anxiously waited for days, until she received a call from the Las Vegas Coroner. Melissa James was the charred body found in the back of Kelly Ryan's torched Jaguar.

The home she desperately wanted to leave behind became a haunting crime scene for detectives. Melissa was found in that trunk in the middle of the desert, but her horror started inside the house of Craig Titus and Kelly Ryan. Police say it began with Kelly zapping Melissa with a Taser gun. And using this kind of "ticker-tape" from the gun itself, cops claim they were able to trace each time the Taser was used.

"We knew the exact moment in time the Taser was fired five times," said Det. O'Kelley. "That time matched up with the time Craig Titus was on his cellphone. We believe Craig Titus was in another room, not with Melissa and Kelly."

O'Kelley says after enduring 50,000 volts of electricity, tiny Melissa had to fight off Craig Titus -- 242 pounds of pure muscle -- in a violent rage.

"There's a bathrobe tie around her neck, there's also speaker wire, double-stranded speaker wire that was wrapped around her neck as well," said Det. O'Kelley. "At autopsy there was evidence of strangulation involved. Even with the extensive burning the medical examiner was able to say that. We also had from above her eyebrows to below her lower lip, her entire head was encircled with duct tape."

The coroner's report also reveals a toxic level of morphine injected into Melissa's leg. Craig and Kelly tell cops they did not kill Melissa, claiming she injected herself, causing a fatal overdose. Assistant District Attorney Robert Daskas says it's one of many lies the couple told trying to create an alibi.

Police claim friends say a panicked Craig called them in the middle of the night claiming they found Melissa dead. Craig then handed them a mysterious duffel bag.

"Eventually they looked inside the duffel bag, they were curious, there was a Taser gun, stun gun and some other stuff," said Daskas.

Police say Craig Titus then called on another friend, Anthony Gross, to help him get rid of Melissa's body.

On surveillance video, you can see Anthony Gross walking into a convenience store at 3:40 in the morning just a few miles away from where the Jaguar was torched in the desert.

At about the same time, not far away, video inside a Walmart shows Kelly using her credit card to buy seven bottles of lighter fluid. Outside, you can see Craig pull the Jaguar up front. He helps Kelly load the lighter fluid in the back seat because, detectives say, Melissa's body was already in the trunk.

After the Jaguar was torched, Det. O'Kelley says in their mad dash to escape, Anthony Gross left a key piece of evidence behind.

"It was a clean flashlight sitting on the side of the road near the Jag located here. It was significant later on to find out that Anthony Gross was involved," said O'Kelley.

Detectives checked his credit card and found Gross had just bought that same make of flashlight. That was enough to haul Gross in for questioning. But when cops went back to Craig and Kelly, they were gone.

"We found out Craig traded in his truck for a brand new Viper truck, so it didn't match the vehicle description we knew he had," said O'Kelley. "Then the two of them took off across the country. They took money they had in the house secreted in little fake canisters."

A nationwide manhunt is launched. The FBI is called in, and then detectives get a tip and track the power couple to an area just outside Boston.

SWAT officers are seen on security video moving in and arresting Kelly in a beauty salon while she was getting her nails done. Craig was arrested a few blocks away. Their capture sent shock waves through the bodybuilding community.

Even behind bars the muscle stars keep making headlines.

While Craig Titus is in the Clark County Detention Center, someone tips off guards about a possible jail-break. Video from inside the jail shows guards aren't taking any chances with such a powerful prisoner, strapping Craig into a chair to transfer him to another pod.

Even though Craig and Kelly are behind bars, their killing spree may not be over. Police claim Craig is trying to arrange a hit, but police are five steps ahead of him, with an elaborate sting to catch him with blood on their hands.

Ron Brady always wanted to be a bodybuilder, and idolized Craig Titus. Brady met his idol in jail and says he was easily lured in when Craig confided in him about the murder of Melissa James. The former man of muscle claimed he was innocent, and he wanted Brady to help him prove it -- by silencing key witnesses.

"He'd asked me to help expose the wrongdoings of these people that were trying to testify against him, but never to have them harmed in any way," said Brady.

Ron Brady claims he was stunned. Here is Craig Titus, one of his heroes, now pleading for his help.

"I don't know where my mind was at, after Craig told me the situation," said Brady. "He was crying, actually crying to me."

Ron Brady, speaking here for the very first time, confesses he wanted to help Craig beat the murder wrap. Soon after his conversation with Craig, Ron Brady claims he was approached by another inmate, Deem Cassim, and he claims that's the first time he heard any talk of getting rid of witnesses.

When Brady was released from the detention center after charges against him were dropped, Cassim kept calling from jail to make sure he was still working on a hit to wipe out witnesses.

Police say Craig Titus was desperate to get himself and Kelly out of jail.

What Craig Titus didn't know is Deem Cassim is secretly working with police to foil the murderous plot.

Craig Titus has been locked up for 10 years for the murder of his former assistant Melissa James. His now ex-wife Kelly Ryan could be paroled next year, but Titus has up to another 30 years in prison. He has not spoken on television since his conviction, until now.

He denies having anything to do with the murder and goes on to reveal for the first time: "I wasn't even present when Melissa died in my home. The women were together after the fight, I was gone."

Craig Titus has a new attorney and is trying to appeal his conviction.

In a letter to me, Craig writes, "I signed a deal I never should've signed."

Craig Titus got up to 55 years.

Kelly Ryan cut a plea deal for arson and assault and battery with a deadly weapon.

Crime Watch Daily could not reach Kelly Ryan or her attorney to confirm the claims she was home alone with Melissa James when she died.

Kelly divorced Craig while in prison. She could be paroled next year. If not, she's set to be released with time served in 2018.

Prosecutor Robert Daskas says because much of the evidence was destroyed in the fire, the coroner had to rule Melissa James's cause of death "undetermined." But Daska says there's no doubt what happened to her.

Daskas says the common thread for all the lives destroyed in this case is a friendship with Craig Titus.