The Unit enters the SERE (Survival, Evasion, Resistance Escape) training course and they are lead to believe that they will be guards. The group is soon shocked to discover that they are actually the POWs for an undetermined amount of time.

The team follows a scientist who may have been targeted by terrorists, hoping to link those same terrorists to a presidential assassination plot.

The crew must fly to Afghanistan to assassinate a high ranking member of the Taliban. However, one of their team helicopters ends up going down in enemy territory, placing the entire crew in jeopardy. Back at the base, Molly confronts a friend and retired Unit veteran about his addiction to painkillers and Kim ends up getting a job at the local radio station.

The Unit ends up detaining a former Yugoslav general who was wanted for war crimes and then allows lets the U.N. take credit for their capture. However, the criminal soon escapes U.N. custody and he is now seeking retaliation against Jonas for capturing him. Meanwhile at the base, Tiffy is convinced that Mack has decided to re-up with the Unit and she's thinking of divorcing him, and Kim is the recipient of some disturbing news.

The Unit is a covert team of U.S. Special Forces operatives who must undertake missions around the world. The latest newcomer is Bob Brown who joins Jonas' team and they set out to rescue an airliner filled with European businessmen who have been hijacked by terrorists. Meanwhile, Bob's wife Kim is struggling with how much control the Unit has on her own personal life.

Jonas and his team must track down surface-to-air missles before they are smuggled out of Brazil after a deal with a drug lord falls through. Jonas gets help from a local boy who informs the team where the SAMs have been taken to be shipped. Meanwhile back on the base, Kim ends up causing even more trouble when she insists that the “Family Readiness Group” deals with what she deems more serious issues. Also, Williams tries to find a way to tell the woman he wants to marry that he is actually a Unit member and not a clerk on the base like she believes.

After Bob gets his cover blown in Africa, he tells Jonas to cancel a visit a dignitary is taking to the area because of the danger. However, the official refuses and something shocking is quickly learned about why he really wants to go there. Meanwhile, Kim has an encounter while at the radio station and Molly gets offered a real estate opportunity.

The Unit is sent to Los Angeles to protect Mexico's drug minister who has been threatened with assassination and soon his wife and sons are kidnapped. At the base, a former Unit wife makes a return appearance in the hopes of luring the Unit members away. Tiffy is upset when Ryan orders Mack to take time off.

The Unit must try to get a listening device to an agent inside the Iranian embassy where U.S., Iranian, and Russian diplomats are meeting. Many are speculating that the Russians are attempting to sell the Iranians material to make a nuclear weapon. Meanwhile at the base, Tom tries to end his affair with Tiffy but she won't listen to him and Kim notices Tiffy at a motel room and does not know what she should do.

The Unit is called in to consult on a bomb planted in an Atlanta bank, but they soon learn that the bomb might be nuclear. Meanwhile, Bob and Kim decide to take a much needed vacation, but Kim soon discovers that Bob has whisked her away on a mission and wants her to help him out.

The team, minus Bob, are in search of a fallen Chinese satellite. This quickly turns into an opportunity to capture one of the world's most wanted terrorists. Meanwhile, Bob is questioned about the Unit's role in the rescue of the hijacked plane. Molly decides to visit the Unit's psychiatrist about the shooting at her home. Kim is frustrating about moving and then comforts a woman who has just learned her husband has died in combat.

Jonas attempts to rescue a group of American missionaries in hiding in Indonesia. However, he soon realizes the mission is going to take more manpower then he expected. At the base, Mac ends up being shot by Bob during a training exercise and Molly, Kim and Tiffy prepare to host a visiting senator.

Jonas and the team carry out an assasination of a terrorist in Spain. However, they soon find out that the government called off the mission and will now not protect them in the country which means there only hope is to escape. Back at the base, Molly learns that her daughter Betsy wants to drop out of college and Kim thinks about taking a college course herself.

Keith Soto returns to the base for a reunion and it's quickly discovered by Jonas and Col. Tom Ryan that he is a newspaper reporter who is writing an article that will expose the Unit. Jonas decides there is only one way to get him to not print the story. Meanwhile, with some help from Tiffy and Kim, Molly tracks down the woman who scammed $40,000 of the women's investment fund.

Unable to communicate with the outside world, the Unit and their families must survive when a deadly gas poisons anyone in their community who steps outside.

The team is sent to Pakistan to help an undercover operative foil a terrorist attack on many cities. On the home front, Molly and Tiffy help one of Tiffy's former students and Kim and Bob welcome a new addition to their family.

A former member of the Unit is locked up in a Bulgarian prison and Jonas and his team must go to help him escape in order to find one of the world's leading arms dealers. On the home front, the women meet a young man who hopes to be part of the unit someday. However, in order to get extra money to take care of her aging mother, Molly takes a one time recruiting job to hire the man away form the military. Needless to say, members of the Unit family are none to pleased at Molly's new job.

A mission is put on hold in South America because the team has to rescue to two members trapped by snipers. Meanwhile, the wives take on a mission of their own to help a unit widow.

The men are working on tracking down a known terrorist before he can launch an attack. At home, the women must face their own danger when a stranger approaches one of the children.

The Unit finds itself torn between saving an African dictator or innocent people when they are sent into a hospital as a hurricane hits.On the home front, Mack and Tiffy reconnect with each other.

The team is assigned to stop of shipment of smuggled diamonds and Bob is conflicted when he sees one of the men helping themselves to the diamonds. On the home front, Molly and Kim are raising money to help the men and women serving in Iraq. Tiffy debates the war with protesters from a local school.

Jonas and Bob, on personal time, rescues a young girl from a cult leader as a favor to an old friend. Tiffy covers for Charlotte and finds herself in a lot of trouble.

While struggling to keep himself and his translator alive after their helicopter crashes in Siberia, Bob remembers the process in which he went through to become a member of the Unit.

Colonel Ryan becomes under scrutiny from a Congressional committee in Washington. Jonas and the team work against an oil minister in South American. On the home front, Molly works with Kim in finding a babysitter for the children.

Jonas heads off to the Democratic Republic of Georgia and finds himself in trouble. On the home front, Mack and Tiffy are fighting her legal troubles and Colonel Ryan is going head to head with the vice president's men.