The Last Saturday(1993)

Original title: Последняя суббота

A soldier returns from the army with his young wife. A local heartbreaker and a drunkard, an imposing man who does not care about anything, takes a fancy to her. He draws the young man into his company, and one evening the wife finds her spouse drowned in a puddle. After some time, she offers the heartbreaker to drink champagne together (and he has previously made her very explicit offers) and tries to kill him, but instead gets a fatal stabbing herself.