The team scrambles to make sense of the disintegration of the unit. The unit reunites to rescue Mack and clear their names. Nerve gas is stolen and the team is sent to retrieve it. Jonas tests his daughter's strength and conviction when she decides to enlist. The team deals with a loss and Jonas vows revenge.

They are The Unit, a covert Special Forces team operating outside the usual military chain of command, risking their lives on undercover missions at home and abroad. Their identities are highly classified, a secret that's also fiercely guarded by their wives. But despite the men's determination to protect their families from the dangers of the job, they've learned that the enemy they have defeated in the field is also capable of bringing the fight right back to their own front door.

The Unit is a covert Special Forces team that operates outside the military chain of command. They are on the front lines, protecting U.S. citizens and foreigners alike, risking their lives daily in the process.

Risking their lives on deadly undercover missions around the globe, the Unit is a highly skilled, ultra-secret contingent of special forces soldiers operating outside the traditional chain of military command.