Britain's Got Talent audition horror after escapologist almost drowns live onstage

David's involvement in the act backfired, leaving Simon nearly pulling the plug. Photo / ITV

A magic act performed during auditions for Britain's Got Talent caused horror after an escapologist nearly drowned in a tank on stage.

The illusion, which took place at The Lowry in Manchester last week, involved the four judges, Simon Cowell, Amanda Holden, Alesha Dixon and David Walliams, who were each given a key by an assistant.

The aim was for the escapologist to be left with the correct key to be able to un-cuff himself while underwater in a tank.

All four judges were given items to help unlock the tank. Photo / ITV

One by one the keys were eliminated while the escapologist was submerged underwater.

Eventually, Walliams' key was the last one left, but things descended into chaos after a fatal error was realised.

Walliams was not asked for his key before the assistant returned to the stage, and it was instead left on the judges' table.

The illusionist was left distressed as he realised he wouldn't be able to escape, but the audience thought it was all part of the act.

Medics were called in as the act was nearly halted. Photo / ITV

A source told Metro UK: "It was horrible. David looked absolutely mortified as Simon started trying to signal producers to stop the production, and a medic was called in.

"It looked like it was part of the act to begin with, but it soon dawned on everyone that it wasn't," they added.

"That this was a real problem that threatened their safety.

"Thankfully they were able to correct themselves but there was a real moment where we thought it could end in disaster and it was clear everyone was beginning to panic."

Simon Cowell has reportedly threatened to pull the plug on Britain's Got Talent auditions after the dangerous act almost ended tragically.