: Filming took place in Moscow, St. Petersburg, and Kislovodsk. Episode Schedule (Season 4) Шифр (телесериал) - Википедия
: The season was filmed without the lead actor following his tragic death in 2022. His character, Proskurin, remains "behind the scenes" to maintain the story's continuity.
: Katerina discovers a broken female fingernail with bright polish on the back seat, leading to suspicions that a woman was behind the wheel. : Filming took place in Moscow, St
: Anna and Sonya discover Polina had secret ties to the "stilyagi" (Soviet youth subculture) and had recently changed her lifestyle.
This episode is the penultimate chapter of the series, focusing on the murder investigation of : His character, Proskurin, remains "behind the scenes" to
: Police locate the car used to hit Nikitina.
: Season 4 is the concluding chapter of the original project. This episode is the penultimate chapter of the
: The car's owner, actor Karpilovsky, is cleared as he was out of town. His wife and mother-in-law do not drive, leaving a mystery as to who broke into his garage.