A fészek melege (1988)

A young woman really wants her husband's dad to move together with them, because they intend to buy a house at the Lake Balaton on the money they would get if the house of the father-in-law is sold. Just not to make this happen, he announces his coming marriage with a woman, whose he in love with, so the house won't be sold. The woman makes her brother to spy on the old man, find out who is the future wife, and betray her. The old man who guesses what they are up to, sets a trap.