Plot summary
Ryan allows one of the rogue agents, Mia, to continue her undercover mission to infiltrate Third Wave, a domestic terrorist group who stand against the "tyranny" of the first world. After Mia is arrested from an FBI raid, Alex and Nikita break her out of prison. However, Mia turns on them and wounds Alex, revealing that she lost faith in Division and joined Third Wave's cause. Division later finds Third Wave's compound and raid it. Mia awaits and straps herself with a bomb to allow the leader, Joshua, to escape before overpowering Nikita.
Despite this Nikita still believes Mia can be saved. Birkhoff finds several foreign bank accounts affiliated with Joshua, and was paid to attack a United States senator. Nikita stops Mia, who reveals another terrorist is carrying the bomb. Nikita convinces her that Joshua is corrupt like Percy was and they work together to stop the would-be suicide bomber, but Mia is killed by Herek's guards in the process. Meanwhile, Michael and Sean take down Joshua and his private security guard partner.
Credits
Adapted from Wikipedia contributors, Nikita season 3. HTML formatting and reference markers removed.