A popcorn warmer caught the popcorn on fire Friday night at Desert Sky Cinema in Sahuarita.
Employees put out the fire with an extinguisher before firefighters arrived.
The fire was contained to the machine, which a Green Valley Fire District spokesman said could cost about $9,000 to replace.
A theater employee said Saturday that the food services area needed to be inspected before selling food and that he expected that to happen this morning. There will be popcorn.
The fire happened about 9 p.m., and nobody was evacuated from the building.