Zinaida Preobrazhenskaya is a mid-ranking official at the US-Canada Institute who defects to America. She is later determined to be a spy by Stan and Oleg, who want to trade her in a prisoner exchange for Nina. Zinaida is arrested and sent back to Moscow, but she is traded for someone more important than Nina.
When Oleg tells Stan he's convinced Zinaida is indeed working for the Soviets, Stan records their conversation and gives the tape to Frank Gaad. Later, the CIA uses the tape in an attempt to blackmail Oleg, much to Stan's regret.