OA is forced to confront one of his biggest fears when the team discovers that deadly sarin gas may have been sold to terrorists.

When an officer is shot dead at a pawn shop along with the store’s owner, the team tries to figure out why a young, recent Ivy League dropout is tied to the crime.

The abduction of a young woman leads the team back to a cold case from 18 years ago, which pushes Isobel to reconnect with her old partner Jake and take another shot at solving one of her first cases in the bureau.