Firefighters responded to what seemed to be regular alarm Wednesday night at the Yard House Restaurant in Denver.
A sprinkler was activated, not by a fire, but by a man hitting it as he fell from on top of the ceiling to the small area between the walls of the restaurant.
"Police say it appears the man had been living in the ceiling for quite some time," a local reporter said.
Firefighters eventually heard moaning in a wall, where they found the man.