After the brutal murder of Nikki Whitehead in her home, police come to suspect she may have known her killer, using closed-circuit television and polygraph tests to discover the truth.

The body of a woman who failed to return from work the night before is found in a churchyard at dawn, and police turn to the city's surveillance cameras to catch her killer.

In Tempe, Ariz., millionaire entrepreneur Rick Chance is gunned down in a hotel room, prompting detectives to analyze a surveillance video to catch his killer.

Keith Reed is found gunned down on his doorstep. What seems like a possible crime of passion is turned on its head after a surprise discovery. Surveillance footage helps police unravel the mystery behind Keith's death and just who killed him.

Grainy security footage reveals what happened to 19-year-old college student Katie Poirier who vanished while working the graveyard shift at a gas station.

Fifteen-year-old Elizabeth Ennen is seen for the last time when a family friend drops her off at home, but her mother says she never walked through the door.

In Coral Springs, Fla., Surya Toha vanishes without a trace after dropping her sons off at school, then chilling video surveillance footage reveals exactly what happened to her.

In 2012, University of Florida Freshman Christian Aguilar mysteriously vanishes from campus. His girlfriend, father, and best friend are in turmoil. Police have nowhere to turn - until a CCTV recording turns the case in a shocking new direction.

When 22-year-old college student Dru Sjodin vanishes following her shift at Victoria's Secret, investigators turn to surveillance camera footage to reveal the chilling reason for her disappearance.

After nursing student Michelle Le vanishes without a trace, police discover footage that shows her car circling the parking lot where she disappeared, but they cannot identify the driver.

Missing 21-year-old student Mickey Shunick's family mobilizes the local community to help search for her, then police spot her on a surveillance video.

The disappearance of 19-year-old college student Kenia Monge is investigated. Included: surveillance footage reveals what happened to her.

After 24-year-old Amy Lord is found stabbed to death, police trace her movements using footage from five different ATMs in Boston.