When an acquaintance of Sue's sees who she thinks was a concentration camp guard in World War II, Sue begins to investigate, looking for the man with little evidence to go on. Meanwhile, Myles, Bobby, and Dimitrius battle against Randy over travel expenses.
Sue meets Jack and Bobby's FBI Mentor when he brings the team in on a case to sting a North Korean terror group - but Sue discovers that things are not as they seem. Meanwhile, Lucy reconnects with her old high school love - with surprising results.
Sue and Dimitrius put an operative in the field to take down an illegal arms sale - but when the encounter gives them a chance to land an even bigger fish, Dimitrius goes undercover as the bait. Meanwhile, Dimitrius wife Donna has some unexpected news of her own.
Sue and the team must infiltrate a Chinese drug-smuggling ring, requiring Bobby to go undercover at the gang leader's nightclub - as an Elvis impersonator. And Sue learns that her friend Troy has an estranged brother - and that the estranged brother has a secret.
When the members of a think tank are found shot dead, Sue and the team track down the sole survivor - but is he a possible future victim or the murderer? By accident, Sue ends up in the fleeing man's car. And Sue teaches Levi some new tricks - or maybe he's teaching her.
Investigating a 5-year old murder, the team automatically links the killing to a group of drug dealers, but further investigating draws them towards another killing that occurred just months before the first. Meanwhile, Myles attempts to improve his neighborly relations.
In order to solve a case involving two men shot with the same gun, Sue and Jack go undercover to the law firm that the two men both worked at. With Myles' sister also working at the law firm the agents get deeper and deeper into the facts of the case.
When the F.B.I's special assistant Howie claims to have nearly escaped being shot, Jack and the team are skeptical as to the legitimacy of Howie's story. However Howie's tale becomes more and more plausible as other killings arise, all linked to Howie's incident.
Seven Eastern-European terrorists in the D.C area are under suspicion from the F.B.I team who have linked them to an underground organ dealing business. In the meantime, Sue and Lucy struggle to live with Nina, their unannounced, and very picky, house guest.
When a radical environmentalist group blows up an SUV, the F.B.I looks into the case with the help of a victim from one of the environmentalist group's earlier fires. Meanwhile, with his cholesterol off the charts, Myles decides to make some changes to his dietary lifestyle.
A special undercover agent from San Diego comes to D.C to assist in an operation involving street drug dealers. But Jack quickly becomes annoyed with the new agent when he starts to show interest in Sue.
A famous actor visits the F.B.I to observe as the team tracks down a gang involved in selling fire arms. Later when the team gets word of a possible terrorist threat, the movie star begins to show interest in Tara.
When several 30-year old women are murdered in a similar fashion, the F.B.I team suspects a serial killer. At first their chances of catching the killer seem bleak, but then the murderer makes contact with Sue and leads her through his own game of Simon Says which will lead them all to him.
When the husband of Sue's friend, Carol, is killed in a boating accident, the team begins to look deeper into the couple's marital history. Meanwhile, Bobby and Myles escort two witnesses on a long, and troublesome, road trip to Arizona.