The Last Hungry Cat (1961)

Sylvester Cat slips when making a grab for Tweety Bird in Granny's flat, and falls dazed to the floor as one of Tweety's feathers lands in his mouth. Tweety runs off. Sylvester comes to and finds the feather lodged between his lips. He thinks he has swallowed and killed Tweety and suffers terrible remorse as an Alfred Hitchcock-like voice-over chides him for his "crime". Sylvester cracks, runs into the streets confessing, and returns to Granny's place, where he finds he didn't eat Tweety after all.