The Unit: Season 4

Home-bound from a five-month mission, the team is called back into action when the vice president is assassinated and the president-elect goes to ground after his motorcade is attacked. Back at home the women are abruptly uprooted when it's feared their lives are in danger as well, and the resulting chaos reveals a deep secret.

While the women try to adapt to their new lives, the team sets a scientist up as bait, triggering the hijacking of their plane.

The team tries to retrieve plutonium in Kosovo, and Jonas is forced into an ethical dilemma when he uses a sex slave to gather information. At the unit's new home base, Tiffy and Abby both face challenges at their new jobs.

The team runs concurrent missions in Columbia, but when congress gets involved there's a risk one of the operations will be left high and dry without a means of extraction. Back at home, the women run their own cover operation when a slip-up by Lissy causes the principal to suspect she's dangerous.

The team is tasked with retrieving Dr. Rocha's family before he'll give up a terrorist target, the women are finally told the true reason for their displacement, and Jonas helps Molly with an assignment.

The team and Bridget play a complex mind game with a suspected terrorist. Back at home, Mack plays a game of his own to force the truth from Tiffy.

Mack's justice is delayed when Jonas' daughter, Betsy, goes MIA in Iraq and Col. Ryan joins the team trying to find her.

Lives and careers are put on the line as the team crosses into Syria to rescue Betsy.

The team encounters numerous complications while delivering a bride - and a horse - to fulfill a brokered peace treaty in Afghanistan. At home, Bob and Kim begin a deeper operation with Isaac Reed.

The team is held hostage by a D.O.D. Under-Secretary's demands that they fulfill a mission without the usual planning. At home, Kim is dismayed when she's told she has to return to Isaac Reed's home, and Bridget Sullivan faces a reckoning.

The team takes Dr. Metz into combat to rescue an embattled president, Charles meets the woman of his dreams - and more trouble than he could dream, and Kim reaches the breaking point.

The team plays a deep game in Macau, negotiating the return of a member for the return of a CIA asset, but the price may be too high. At home, Kim is called into service yet again when Isaac Reed refuses to speak to anyone but her.

Jonas and Mack have a mystical experience when one is injured and the other is charged with stealing a valuable spear, Kim gets more than she bargained for when she accompanies Bob on a mission while he's in withdrawal.

Jonas accepts on off-book assignment from the new president, which success depends upon the team successfully eluding an Israeli hit squad. Elsewhere, Ryan's promotion opportunity brings back memories from his youth.

A training mission with a new recruit goes horribly wrong, sidelining the team just as Hector's killer is found. Meanwhile, Betsy's issues with her cover interview cause Jonas to help her prep, and Molly to worry about the stress she's experiencing.

Chlorine gas is used in an attack on the town, leaving Tiffy to save herself and her students, Mack and Bob to secure the apartments and Charles stranded on the road, while Sam and Jonas desperately try to locate the source before all the oxygen is gone.

The team's mission is endangered when a sniper downs their helicopter, giving a death squad enough time to close in on Jonas' friend who they're to rescue. Back home, Ryan takes on a cover when he preys on an addict for information, and Joss finds Charles.

The team combats domestic terrorism...from inside out.

When a team member assaults one of the unit's own, Jonas begins a manhunt that will change the team forever. Meanwhile, Mack has to face his demons in order to reach a woman who's taken a sick baby.

A random incident throws Jonas and Bob's carefully planned mission into chaos.

While Jonas is tracking down a Russian terrorist cell, Molly is used as bait.

The Unit must locate and diffuse three sets of dirty bombs headed for unknown locations across the United States.