It might be hard to image two movies with less in common than Fifty Shades of Grey and The Spongebob Movie: Spongebob out of Water, once cinema worker managed to mix up them up, much to the displeasure of local parents.

The cinema in Loveland, Colorado accidentally showed the beginning of the steamy adaptation to a room filled with children at an 11.45am screening.

Grandparent Joe Jaramillo told The Colorado that parents quickly realised something was amiss and hurried out as quickly as possible:

"It was the parents' reaction to it that was so funny.

"Some were moving pretty fast to get the kids out of the theater. The family sitting behind me said what I was thinking: 'Am I in the right theater?'"

When questioned by email, Metropolitan Theatres President David Corwin simply wrote "There's no story here."