Maybe he should have just 'Let It Go'? Sorry.

Simon Cowell has seen some horrendous acts on the various talent shows he has judged on over the years. But it's not very often that they're so bad that he feels he has to leave.

That's what happened on 'Britain's Got Talent' last night when double act Katherine and Joe performed as Elsa and Sven from Frozen and sent him over the edge. Cowell was already in a bad mood from 'Chucklefoot', the previous act, who he said 'weren't his cup of tea'. Katherine and Joe's performance, as you'll see below, really didn't help matters.

Check it out here:

"I'm not being rude, but what the bloody hell was that? I don’t know what that thing is… he's not a bloody moose!", Cowell said of Joe's questionable outfit.

However, fellow judge Amanda Holden disagreed with Cowell's criticism after hearing the reaction of the crowd.

"You know Simon's been saying the most important thing about 'Britain's Got Talent' is listening to our audience. That is your public, Simon," she said before Cowell stormed off.