A bad day gets worse when Sarah throws Chuck a surprising relationship curveball as the CIA orders Vivian Mc Arthur Volkoff (recurring guest star LAUREN COHAN) assassinated. In order to prove Vivian's innocence, Chuck must put his trust in a dangerous ally: her father, Alexei Volkoff (recurring guest star TIMOTHY DALTON). Meanwhile, Ellie suspects that her mother (recurring guest star LINDA HAMILTON) is interfering with the search into her father's past.