Dennis sneaks out on his sitter to go to the movies where his parents are and causes trouble at the theater.

After a truck knocks over a street sign, Dennis and Tommy set it back up--incorrectly. As a result, Mr. Wilson gets a hole dug in his backyard for the swimming pool that was intended for the other address.

Dennis introduces his visiting grandpa to town spinster Miss Cathcart, who takes an interest in him, sings for him, and pretty much makes him miserable.

Dennis thinks that his dad is in money trouble so he starts out selling bottles and before you know it everyone in town thinks that the Mitchell's really are in trouble with money.

Dennis takes care of a dog named Charlie who inadvertently wins a prize for a painting that Mr. Wilson painted after his tail brushed the painting.

Dennis wants his dad to be a hero so bad after Johnny Brady's dad always seems to get his picture in the paper for some heroic act. So Dennis tries to talk to the town reporter to put Henry's picture in the paper and make him a hero.

Dennis and a boy that Mr. Wilson was responsible for are left without a babysitter after agreeing to let one sitter sit for the boys cause Mr. Wilson and Henry both end up canceling theirs.

New neighbors, the Driscolls, share a party telephone line with the Mitchells, which causes problems for both families.