: Irina discovers that Bobrov's girlfriend was involved, noting her nail polish matches a fragment found at the crime scene.
: Anna realizes that Bobrov wrote an anonymous note to Nikitina's father and planted a poem in the coffin. : Irina discovers that Bobrov's girlfriend was involved,
: The "cipher girls" successfully solve the case despite heavy pressure from their supervisor, Marina Korzun. : Irina discovers that Bobrov's girlfriend was involved,