: 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.
: Season 4 is the concluding chapter of the original project. : The season was filmed without the lead
: 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. : The season was filmed without the lead
: Anna and Sonya discover Polina had secret ties to the "stilyagi" (Soviet youth subculture) and had recently changed her lifestyle. : The season was filmed without the lead
: Katerina discovers a broken female fingernail with bright polish on the back seat, leading to suspicions that a woman was behind the wheel.