Chuck Versus the Undercover Lover

Chuck discovers that many Russian arms dealers are secretly meeting in Los Angeles. One particular Russian woman catches his attention, and he flashes on her as being Agent Casey's ex-girlfriend. Chuck grows very intrigued and begins to pester Casey about their history. After learning this woman is to set marry one of the Russian arms dealers, Chuck insists that Casey fights for his woman. Will Casey fight for his true love without compromising his identity? Meanwhile, Captain Awesome and Ellie reach a tough point in their relationship.