Sasha and Olya are getting married. Pchyola, Fil and Kosmos give young people an apartment as a gift. But on their wedding night, the young people almost die because of a stretching trap, to which a grenade is attached. Sasha notices the threat in time and almost manages to neutralize it, but because of the neighbor's dog, the grenade falls, and Sasha throws it down the stairs, where the explosion occurs.