While the third season aired in late 2022, the 16-episode fourth season premiered on streaming platforms like Wink and Kinopoisk in March 2024 and on Channel One in October 2024.
This season focuses on how the women adapt following the departure of Lieutenant Colonel Proskuira (played by the late Sergei Puskepalis). While the third season aired in late 2022,
Sonya infiltrates Shefner’s apartment looking for a connection to the victim. She discovers missing military books from Volynin's home and a note in Shefner’s diary confirming a meeting with him on the day he died. She discovers missing military books from Volynin's home
In the Russian retro-detective series ( Шифр ), Season 4, Episode 7 (broadcast/released in 2024, continuing the series from 2022), the investigation into Volynin's death deepens with unexpected twists and personal risks for the main characters. Plot Summary: Episode 7 Episode 7 (broadcast/released in 2024