Magoo's Lodge Brother (1959)

Near-sighted Mr. Magoo is on his way to his lodger-convention and latches onto a robber, whom he thinks is his room-mate. He winds up in the den of the thief thinking he is in his convention hotel room. He proceeds to toss around in fun dynamite, hand-grenades and bombs until the crook is knocked out and captured by the police. Magoo becomes a hero.