Sid and Henry

Sid and Henry are a pair of mud-dwelling pigs who appear erroneously in an edition Monsterpiece Theater, where the program attempts to present One Flew Over the Cuckoo's Nest.

One of the features played instead is Four Flew Over Pigsty, Land in Mud. In the film, Sid witnesses what appears to be a flying number 4 overheard. He asks Henry if that's possible; Henry responds in the negative. The winged 4 immediately lands in their slop, prompting Sid to remark, "I didn't think so."