Adam Kaufman is brought into CTU as an analyst. He assists CTU by cracking several codes, extracting files, and locating the site where terrorists have planted a bomb. He develops an adversarial relationship with Chloe O'Brian in the third season because Chloe thinks he cannot work with women due to his abrasive personality. He is personally shaken when he learns that his sister is infected by the Cordilla virus, which kills anyone who contracts it.