
Eagle-eyed technical experts prove there is no such thing as a perfect crime as they assemble the pieces every criminal leaves behind. Dramatic crime re-creations and, sometimes, part of the investigations are a staple of the series. Some of the re-creations include alternate versions of the crimes, which are disproved by science. The show's episodes follow each case from the initial investigation until it reaches its legal resolution.

A flawed envelope is an unlikely clue to identifying a killer who laced a water cooler with cyanide and caused the death of a woman.

A man denies killing a pedestrian in hit-and-run, claiming he sold the car in question; authorities track down the car to find critical evidence.

Detectives discover new clues left by a stalker's letter to his victim.

Three years later, a second autopsy determines who's right when a medical examiner and detectives disagree on the cause of death.