Robin Cunnings was a rogue CIA agent and is portrayed by Rebecca Romijn of
X-Men fame. She appeared in the fifth season episode, "Chuck Versus the Curse".
Cunnings was a pawn of a conspiracy plot by Daniel Shaw and Clyde Decker to destroy Chuck Bartowski and his spy firm, Carmichael Industries. She is known for her extended torturing skills, although she "prefers to think of it more as an art form".
Her favorite interrogation technique has been electrocution with a device she dubs as "The Toy".
Robin Cunnings was introduced as the successor to the late CIA Agent Clyde Decker, apparently continuing his legacy of destroying Carmichael Industries and ultimately Chuck.
She targets Ellie and Captain Awesome as a leverage to convince Carmichael Industries into giving back the Omen Virus. Ellie manages to see through her fake kindness and realized that they were being kidnapped and escapes from her team. However, Chuck willingly surrenders himself thinking they still had Ellie. Sarah and Casey eventually arrive to rescue him and successfully captures her.
While under captivity at Castle, she reveals to General Beckman that she is indeed part of a conspiracy against Chuck - but no knowledge of who the mastermind is. To getting this info, she is ironically interrogated using her own torture device.
Cunnings has since been incarcerated by the CIA.