Russell Dermond's headless body is discovered in the garage of his million-dollar lakefront mansion; his wife, shirley, is found floating dead in the water, her ankles tethered with cinder blocks. One key piece of evidence remains missing.

After 7-year-old Kyron Horman's stepmother drops him off at a school science fair and takes a picture, the little boy is never seen again; his disappearance is one of the largest mysteries and investigations in Oregon's history.

Three young brothers are reported missing the day after Thanksgiving in 2010. In a shocking twist, their daddy claims he gave them to an underground group -- but investigators say his story doesn't add up.

In 2011, baby Lisa Irwin goes missing from her crib in the middle of the night and is never found. Stolen cell phones and a disturbing charge on a parent's debit card adds to the mystery.

6-year-old Timmothy Pitzen vanishes after a three-day trip to waterparks and the zoo with his mom. In a terrifying twist, his mom is found dead in a motel room with a disturbing note by her side.

After leaving a friend's hotel, 17-year-old Brittanee Drexel suddenly disappears during spring break in Myrtle Beach; the case comes alive when twisted and disturbing details start to emerge from a prison cell.

35-year-old Crystal Rogers, a mother of five, goes missing and her car is found on the side of the Bluegrass Parkway with a flat tire and her keys, purse, and cell phone all left inside. But Rogers’ disappearance isn’t the only mystery casting a shadow over Bardstown, Kentucky.

Brian Shaffer, a handsome, young medical student, is out celebrating the start of Spring Break with friends after cramming for medical exams. Brian is clearly recorded on surveillance video entering a bar, but is mysteriously never seen leaving.

Avid outdoorsman Kenny Veach vanishes near the mysterious Area 51. Searchers find his cell phone near a mine shaft, but no sign of Kenny. In earlier, recorded video, Veach describes his body vibrating as he approaches a cave near the same location.

Mother of five, Jennifer Dulos, disappears after dropping her kids at school, but evidence shows a brutal assault in the garage of her upscale, Connecticut home.

College student Faith Hedgepeth is found bludgeoned to death in an off-campus apartment in Chapel Hill. DNA, a threatening note at the crime scene, and a voicemail from Faith’s cellphone could point to her killer.

A raging fire kills Nanette Krentel in her secluded home in the middle of the day. Investigators are puzzled why she was unable to escape, until the autopsy reveals the cause of death was a gunshot wound to the head.

A young police officer is ambushed and shot with a 12 gauge shotgun in the middle of the night on his way home from work, but this isn't the only unsolved mystery in the small and quaint community of Bardstown, Kentucky.