A gruesome mystery washes ashore from the mighty Mississippi River, leaving the chilling imprint in the sand of a headless body. It's a jigsaw puzzle made of flesh and bone.

"We got reports of different body parts that were spread about the beach shoreline, her head, her arms and her legs had been removed," said Hancock County, Mississippi Sheriff's Commander Glenn Grannan.

Commander Grannan shows Crime Watch Daily the stretch of the Mississippi River shoreline in Bay St. Louis, Mississippi, where the chopped-up body parts had been bobbing in the Gulf of Mexico.

"There are theories that the parts were dropped in different places just to keep them all from being found," said Grannan.

The woman's killer had meticulously filleted out pieces of flesh to keep cops guessing.

"Those were tattoos that were intentionally removed in an effort to keep the body from being identified," said Grannan.

"The strike with the knife to the chest was the cause of death."

To solve the case, Mississippi authorities had to bring the dead woman back to life, piecing together her body and her last hours and give her a name.

They get a tip: Right across the state line in Louisiana, a pretty blonde exotic dancer in New Orleans had failed to come home from work. The dancer was 22-year-old Jaren Lockhart, the loving mother of a 3-year-old daughter. It wouldn't take long until a DNA comparison reveals the headless body belongs to the blonde beauty.

"We found some articles of clothing and some other stuff that belonged to Jaren along the beach," said Grannan.

But who killed Jaren Lockhart, and why?

Investigators check the security video at Temptations, the club where Lockhart danced. They catch a mystery couple on the recording. The pair had reportedly been trolling Bourbon Street clubs all night, making a request: They were randomly asking different dancers to go home with them.

"Two were propositioned before Jaren," said Grannan.

Lacy Dillman, one of those two dancers, later told cops in an audio interview that she turned down $700 the couple offered to perform at a bachelor party because they "creeped her out."

"Around 1:30 she said we have to find a girl or something bad would happen. That's when I said I can't leave," Dillman told investigators.

And that's when Jaren Lockhart's luck ran out. Investigators set the scene, saying Lockhart was just finishing her shift. It was a lousy night for tips and the desperate young mother of a 3-year-old daughter is worried about making the rent. So when she's offered the quick cash gig, she jumps at the chance.

"We know Jaren told a dancer friend that she was going to do a threesome and they were going to pay her $700," said Grannan.

The couple that investigators say Lockhart left with is seen on security video. It was the last time Jaren Lockhart was seen alive.

"We were able to track that car," said Grannan. "We knew that car was in Mississippi when the body was dumped."

Authorities release the video to the public for help. Soon they get a tip, and zero in on their prime suspects.

Surveillance video of the fatal night of June 6, 2012 shows Margaret Sanchez and Terry Speaks stepping into the club where Jaren Lockhart worked as a dancer. The couple had promised Lockhart $700 if she would perform at a bachelor party. Friends now reveal they all actually knew each other and had worked together before, so Lockhart had no clue she was in any kind of danger.

"He had actually, would walk some of the girls to their cars at night," said Hancock County Sheriff's Commander Glenn Grannan.

Investigators say Terry Speaks and Margaret Sanchez weren't really looking for a party at their house. They were looking for a kill, and Jaren Lockhart spent her final hours at their house. Inside the couple's home, authorities say one of them pinned Lockhart to the ground while the other stabbed her through the heart, and after they killed her, they chopped her up into pieces.

Neighbor John Slocum saw Speaks dragging garbage bags out of the house before dawn that night.

"I don't know if there was a body in there or what but he was straining putting them in there, put it that way," said Slocum. "It was at least three or four big ones, and he was kind of straining with them, dragging them. You could smell the bleach from over there to here."

Even before that night, Slocum stayed as far away from his neighbors as possible.

"He gave off a lunatic vibe," said Slocum. "I mean that guy, I thought he was sick. How do you do jumping jacks in the middle of your yard in your underwear? And hollering and screaming. I'm like, 'This guy is crazy.' My wife said 'We gotta watch this knucklehead,' and I said 'Yeah.'"

Later, pieces of Lockhart's hacked body were thrown from a bridge and washed up on a beach 60 miles away on the Mississippi Gulf Coast.

Authorities have a lot of legwork to do before they can put either Speaks or Sanchez behind bars. There was no DNA on the body parts, or on the weapon, or at the scene of the crime. And their car had been scrupulously bleached clean.

But what Margaret Sanchez didn't know was her boyfriend's real name: Terry Speaks could fill a phone book with aliases. His own girlfriend knew him under the fake name of "Alan Rice."

Sanchez also didn't know Speaks had been wanted for failing to register as a sex offender. Cops threw him back in federal prison. He wasn't going anywhere soon.

"It took us nearly two years to even get to the point where we could prosecute him," said Grannan.

In custody, Speaks tells investigators he had nothing to do with Lockhart's grisly murder. And he conveniently suffered from amnesia. Speaks was getting notoriety too. In a recorded prison phone conversation, he boasts: "Was I big on the news and all that? I was like just as big as the guy who did the Colorado bombing."

So how did the deadly duo finally go down? Emails -- in fact, hundreds of them, sent back and forth, from Speaks in prison to Sanchez on the outside.

One email from an angry Speaks in prison reads: "You're the one they'll fry and not me." Then he writes: "Remember the boots? Remember the panties? Do you remember what you were wearing? Shall I go on?"

"He threatened to, as he put it, 'Go to the Man,'" said Grannan. "There was some damning information there. He became upset with Margaret because Margaret had indicated that she had found someone else and she was going to get married, and she starts reeling him in back in, you know -- 'I love you,' that kind of thing, knowing that she's got to stay onboard with him so he doesn't give her up."

Speaks briefly represented himself at his own trial. Terry Speaks was found guilty of second-degree murder and sentenced to 100 years in prison. Margaret Sanchez pleaded guilty to charges of manslaughter and obstructing justice. She's is serving 40 years.

"I fully believe had we not be able to arrest them and put them in jail, that it would happen again," said Grannan.