Don Took

Michael is so smitten with Gob's girlfriend that he decides to let her know that Gob has been cheating on her, and Lucille tries to break up Buster and Lucille Austero.

Vaughn gives Sydney an unexpected Christmas gift; Jack acts to save Sydney when Sloane orders her tortured and killed for being a mole.

Vaughn asks Sydney to use her friendship with Sloane's wife to gain access to a book in Sloane's home.

Passion ignites between Sydney and Noah, while Sloane questions Noah's allegiance; Sydney continues to uncover startling information about her mother; K-Directorate dispatches an assassin to eliminate Khasinau.

Ariana Kane (Faye Dunaway), the head of counterintelligence for Alliance, meets with Jack in her investigation of the disappearance of Emily.

Sydney must make a deal with Sark for the antidote to Vaughn's potentially fatal illness; Will's research uncovers troubling inconsistencies involving 20-year-old IQ tests.