A young girl finds scattered envelops in a field, then a postman's satchel, then a hanged man.
Jump 20 years: the girl, now grown, lives with her aunt and has a job with the post office only because her dead uncle was a respected party leader.
She's subbing at a small station when a robber strikes. He takes the loose cash; after he leaves, she finds lots more money in a metal box. She takes it.
Suspicious police assign Ivan, who's from the council, to follow her. He does, trying to seduce her nightly during his surveillance.
She sees the thief again by accident and makes contact.