Strike Up The Band

Strike Up the Band is the one hundred and thirteenth episode from Season 1.

Plot
Alice is watching a soap opera about a man named Rodney leaving his girlfriend Daphne, and crying. That is until she hears unpleasant music. The music came from Dennis and his band playing their instruments loudly. Dennis on the trumpet, Margaret on the cymbals, Gina on the accordion, and Joey on the drums. After Alice tells the kids to stop playing their music, they do so, and Dennis asks his mother what she thought of the music. Alice replies it's different.

Joey says they were playing "Camptown Races", while Margaret says they were playing "Home on the Range", and Dennis says they were playing "On Top of Old Smokey". Alice suggests they share their talents with the neighborhood, and they do so. Upon playing their music, Dennis and friends end up annoying everyone who is nearby due to how out of tune and loud they're playing, even going as far as to make a man mowing his lawn go back into his house, a dog go back into its doghouse, and even getting some workmen into a manhole.

Meanwhile, Henry and Mr. Wilson are at crime watch training and were graduating along with numerous other crime watchers. At this moment, a thief steals a purse from a lady walking by. The chief orders Henry and Mr. Wilson after the purse snatcher, and they set to work. The thief ends up in a department store to pose as a mannequin, so to not blow his cover. When the thief sneezes, Henry, thinking Mr. Wilson was the one sneezing, says "Gesundheit". When the thief sneezes again, Mr. Wilson says "Gesundheit", thus the thief blew his cover, hit Henry and Mr. Wilson with the woman's purse, and continued to make a run for it.

Henry and Mr. Wilson find the thief at a pool table, hitting cue balls at them, making a mess of the store. Henry grabs a bowling ball and rolls it at the thief, only for the thief to get on and land on a springy footballer, sending it flying towards Henry and Mr. Wilson. The thief gets on a skateboard, while Mr. Wilson chases on a tricycle and Henry uses a pogo stick. The thief tries to break for it again when a vacuum stops him from running. The vacuum came from a vacuum cleaner, and the cleaner succeeds in sucking the thief in.

However, there's one problem. Mr. Wilson forgot to turn off the vacuum cleaner, and it starts sucking Henry in. As Mr. Wilson tries to get Henry out, the cleaner sucks both of them in as well as everything in the store, causing it to explode. Due to the explosion, the thief escapes again by breaking through a wall. The thief was being annoyed by Dennis and friends playing their awful music in front of him, thus he couldn't move. Henry and Mr. Wilson arrest the thief, Mr. Wilson gives him the right to remain silent, and the thief explains that Dennis and friends should remain silent.

The robbery makes the news later, much to Alice's surprise. Mr. Wilson admits he and Henry couldn't have arrested the thief had it not been for Dennis and friends. Dennis explains how he helped his dad and next door neighbor by telling Joey, Margaret and Gina to play awful music, thus getting everyone away from them. When Dennis notices everyone is gone, he believes they hate music, but Alice knows the reason.