Sydney (Jennifer Garner) is forced to work side by side with former enemy Sark (David Anders) on their latest SD-6 mission: to steal a vital component of the Echelon Satellite System, which keeps the nation alerted to security threats. Syd's countermission on behalf of the CIA is to destroy the component's hard-drive so that it cannot be used by SD-6; even so, the information must be retained somehow -- and thus, the photographic memory of computer wonk Marshall Flinkman (Kevin Weisman) come into play. Alas, the mild-mannered Marshall is hardly the most competent of spies, and his first mission goes disastrously awry. Faye Dunaway makes her first series appearance as Ariana Kane, head of Alliance counterintelligence, who will stop at nothing to find out who is blackmailing Sloane (Ron Rifkin).