14/08/2014 12:56 BST | Updated 22/05/2015 06:12 BST

Children Waiting To See Disney's Frozen Are Shown Explicit Nymphomaniac Trailer

NYMPHOMANIAC 2013 Magnolia Pictures film with Stacy Martin at right and Connie Nielsen

Parents waiting to watch Disney movie Frozen had to shield their children's eyes when they were mistakenly shown explicit sex scenes from the X-rated movie Nymphomaniac.

The audience in Tampa, Florida, were left gobsmacked when a warm-up cartoon was interrupted by a clip from the art house sex film, described as the most explicit ever to be shown in mainstream cinemas.

Horrified grandmother Lynn Greene, who had taken her grandchildren to see Florida, said: "They put in the filler, it looked like Steamboat Willie, the old Mickey Mouse cartoon, and then all of a sudden it goes into this other scene.

"It seemed like forever when you're trying to, you know, cover a little guy's eyes. I didn't have enough hands to cover his ears too and he got the sound down real good.

"You're talking, what, a PG-rated movie to all of a sudden have an R-rated scene up there for little children? My concern is that there should be safeguards in place so that this doesn't happen again."

Temporarily banned from YouTube for its overtly sexual content, the Nymphomaniac trailer shows Shia LaBeouf and Stacy Martin engaging in various sex acts amid a montage of often violent scenes - which is rather a contrast to Disney's Frozen (just a bit!).

Inspired by The Snow Queen fairytale, it tells the story of a Scandinavian princess on a mission to find her sister, a queen who is unintentionally destroying their kingdom with the power to freeze anything she touches.

Nymphomaniac will debut in Copenhagen on Christmas Day before a likely general release in March in the UK next year.