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A retired man (Jerry Stiller) brings home a fish, puts it into the family bathtub, to keep as a pet. His wife (also his wife in real life, Anne Meara), feels that this is the straw that broke the fish's back, as it were. They argue, and seperate, in the middle of a party in their home. The mother moves in with her son, wife, and granddaughter, and tries to get on with her life. He, on the other hand, doesn't. One or two scenes are worth the price of admission. Consider this a romantic comedy of a different sort.
At first, I thought this would be another glimpse at Frank Costanza, the character that Jerry played in Seinfeld. You definitely get some of that energy here, because, after all, it is Jerry Stiller. There are, unfortunately, too few scenes between Jerry and Anne, but they are good nonetheless. Look for a lot of the smaller roles to be played by actors you know, such as "Bert Buchman" from Mad About You, and Doris Roberts, who plays Ray Romano's mother in Everybody Loves Raymond.
While this is not a great movie, it's great at being a good little film. Quite enjoyable as a Sunday Matinee.