Diff'rent Strokes S04E22 - Lifesavers

Willis saves Arnold's life, so Arnold feels obligated to dote on him constantly. In order to get Arnold off his back, he sets up a fake robbery at his job so Arnold can save him and even the score. When Arnold finds out what Willis is up to, he decides to have a little fun with the "robber," not knowing that a real robber has come to hold up the place.