Unlucky in love, chemist Paul Matthews visits gypsy Madame Rosa for help. Quickly realizing he is a hopeless nerd, she gifts him with Love Potion No. 8, which makes anyone who wears it irresistible to the opposite sex for four hours. Paul and animal psychologist coworker Diane Farrow decide to test it on themselves. The awkward pair suddenly find themselves alluring to anyone they approach, but soon realize they are most attracted to each other.
Eight-year-old Kevin McCallister makes the most of the situation after his family unwittingly leaves him behind when they go on Christmas vacation. But when a pair of bungling burglars set their sights on Kevin's house, the plucky kid stands ready to defend his territory. By planting booby traps galore, adorably mischievous Kevin stands his ground as his frantic mother attempts to race home before Christmas Day.
When Lenny and his wife, Amanda, adopt a baby, Lenny realizes that his son is a genius and becomes obsessed with finding the boy's biological mother in hopes that she will be brilliant too. But when he learns that Max's mother is Linda Ash, a kindhearted prostitute and porn star, Lenny is determined to reform her immoral lifestyle. A Greek chorus chimes in to relate the plot to Greek mythology in this quirky comedy.
Jack Powell suffers from an affliction that makes him grow four times faster than normal, so the 10-year-old looks like a 40-year-old man. After years of being tutored at home, Jack convinces his overprotective parents to send him to public school. The children don't know what to make of Jack, but with the help of his fifth-grade teacher, he makes an effort to win them over.
Bumbling Navy lieutenant Tom Dodge has been given one last chance to clean up his record. But Admiral Graham, his nemesis, assigns Dodge to the Stingray, a submarine that can barely keep afloat. To add insult to injury, the Stingray is to be the enemy flagship in the upcoming war games … and to make matters even worse, Dodge's crew is a band of idiots even more incompetent that he is!
An American gets a ticket for an audience participation game in London, then gets involved in a case of mistaken identity. As an international plot unravels around him, he thinks it's all part of the act.