Nikolai Timoshev was a KGB colonel who trained KGB illegals. While training Elizabeth, he raped her. He later defected to the US and informed the FBI of the Illegals program.

In the Pilot, the Jennings attempted to forcibly exfiltrate Timoshev to the Soviet Union. However, when he stabbed Rob McKenzie, the detour to take Rob to the hospital resulted in the Jennings missing the handoff. The Jennings then kept Timoshev in the trunk of their car in the garage, until they could determine the best course of action. When Philip learned Timoshev had raped Elizabeth, he killed him.

Timoshev appears in one of Elizabeth's dreams where she sees Paige discovering Pastor Tim dead. Tim then turns into Timoshev who begins to rape Paige. This warns Elizabeth that if Tim is killed, Paige will be experiencing a trauma that will affect her life forever, as Timoshev's rape of Elizabeth did.