When a nanny, and the child she took care of, disappear from her employers' home after being fired by them, the team must determine if the nanny is a kidnapping victim, or a kidnapping suspect.

Max Cassidy vanishes after leaving a message on his wife's voicemail, with both Jack and Ann frantic to find him. While investigating, Jack realises that Max was having an affair, and that he's gotten much deeper into a case than he should have following the murder of his partner, Jimmy, a man Max had felt was too green for undercover work. Both Jack and Ann fear the worst as the team tries to hunt down Max.

After the latest lottery winner goes missing, the team works to figure out why.

The team believes that the past of a missing psychologist's brother might have played a role in his disappearance. Martin's relationship with Kim takes a spicy turn.

The suspect list keeps growing as the team investigates the disappearance of a Russian matchmaker.