The Chain Gang (1930)

Mickey Mouse and a group of his friends find themselves on a prison chain gang, overseen by Pegleg Pete. As they toil away breaking rocks, Mickey pulls out a harmonica, sparking a lively music session that gets everyone dancing. Before long, chaos ensues, leading to a jailbreak, and Mickey finds himself on the move, pursued by bloodhounds, including the soon-to-be Pluto, making his debut. In a twist of fate, Mickey tumbles off a cliff and lands right back in a jail cell.