An FBI agent trains and handles agents who go under cover to solve crimes; Joe mourns the loss of one of his own as the dangers of the job become all too real.

Joe enlists the help of his former handler when two of his agents disappear during a dangerous mission. Also, Heather looks after a witness who thinks someone is following her.

Lily goes undercover as an Irish nanny in order to determine the whereabouts of another Irish nanny who has gone missing and is possibly dead. Joe tries to set Darnell up as a collector/enforcer for a high-powered bookie they want to bring down.