They Go Boom is a Laurel & Hardy sound short film released 21 September 1929.
Stan and Ollie try to sleep in a rented room. Ollie, suffering from a cold, coughs frequently, while Stan snores, thus each keeps waking the other. The owner of the room threatens to throw them out. When the duo is back in their room, their air mattress is filled up accidentally with gas and blown up so big that Stan and Ollie are pressed against the ceiling. After they have realized the trouble they are in, they start to panic, at which point the hotel owner and a police officer enter the room. Oliver sneezes and the mattress explodes.
- Stan Laurel as Stan
- Oliver Hardy as Ollie
- Charlie Hall as Landlord
- Sam Lufkin as Policeman