A device that can prevent a nuclear meltdown is tracked through the Los Angeles sewers; Walter learns to listen and not offer advice to Paige; the team meets their new neighbor.
Torres boldly breaks protocol when he learns a witness in an NCIS case is wanted by U.S. Immigration and Customs Enforcement.
McGarrett's first date with Lynn turns deadly when they are targeted by a mob boss. Elsewhere, Chin and co race to prevent a murder.
A high-stakes domestic disturbance involving a father and his two young daughters leads the team to race against the clock to save a group of international activists.
When David Hodges goes missing, the CSI team searches for any piece of evidence that can help locate him, clear his name and save the reputation of the crime lab.