Here's the episode guide for episode 20, "Chuck vs. the Family Volkoff":
IN ORDER TO SAVE THE LIFE OF A FORMER ALLY, CHUCK MUST JOIN FORCES WITH HIS GREATEST FOE-LINDA HAMILTON, LAUREN COHAN, MEKENNA MELVIN, AND TIMOTHY DALTON GUEST STAR-A
- bad day gets worse when Sarah throws Chuck a surprising relationship curveball as the CIA orders Vivian Volkoff (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 (guest star Timothy Dalton).
- Meanwhile, Ellie suspects that her mother (guest star Linda Hamilton) is interfering with the search into her father's past.