You hear Peter (Jack Coleman) splash down into the water, but you can see him standing still when the sound effect hits.
During the morgue scene when Traff (Jamie Harrold) is looking at the corpse of his "twin brother," you can see the "corpse's" eyes twitching.
Maintenance man Jackie Gleason (Tseng Chang) tells Dr. Stegman (Bruce Davison) that Johnny B. Goode (Stephen King) is absent because of his wife's teeth.