Gopher gives his parents a cruise as a Mother's Day present. Gopher's father grows jealous of the close relationship between mother and son. An older couple, who has finally seen its youngest child move out of the house, is stunned by an unexpected pregnancy. A widower's teenage daughters repeatedly reject his new wife, but must rely on her help when they get into a jam in Mexico.

Gopher invites his widowed mother onto the ship in the hopes of cheering her up, but is hurt by her seemingly cheerful attitude, which he interprets as an insult to his father. A group of buddies takes a cruise. One of the men meets a woman who is a regular customer at the restaurant where he works. He lies about his identity because he thinks she would be put off by the fact that he is a waiter. A comic's romance with the reporter who is writing a feature about him appears doomed after she takes offense to his act.

The crew is in Australia to work on one of the cruise line's ships based there. And a wealthy man named Farnsworth (Lloyd Bridges) has decided to invite his whole family for a reunion, but in actuality he wants to see who, among them he should keep in his will.

After having spent time with his family, William Farnsworth (Lloyd Bridges) has finally decided who will be kept in his will.

The crew stages a musical revue, with Gopher and Isaac scripting and relatives expecting to star. Lionel wants Millie Washington to marry her. Gopher argues with Doc over his former sister-in-law Trish, and with Isaac over their script.

Lionel promises to give Isaac an executive position, if Millie marries him. Doc's in-laws help him make up with Gopher. A stranger paid for Victor's passage. The crew's relatives squabble over who's going to star in the musical.