Dennis the Menace S01 E09 The Price of Stardom/Space Menace/The Magic Flute

Dennis is made the prop man for the community theater whereupon he turns a serious drama into a roaring comedy. When Henry takes Dennis and the gang on a tour of his aerospace company, the gang slips away. They find a rocket ship and decide to investigate. Once inside, Dennis hits a button and WHOOSH! they are blasted into outer space.