David Copperfield has been forced to reveal the secrets behind one of his most famous tricks.

They say a magician never reveals their tricks.

Well, if you’re David Copperfield, you don’t have much of a choice in the matter.

The 61-year-old magician was forced to reveal how one of his most famous tricks works by a Las Vegas district court judge.

Copperfield is currently being sued by British tourist Gavin Cox, 58, who claims he was injured while acting as an audience participant in the renowned magician’s “Lucky #13” trick.

A post shared by David Copperfield (@d_copperfield) on Apr 25, 2016 at 6:02pm PDT

Cox filed a negligence lawsuit after a fall backstage caused him a dislocated shoulder, and he claims to have also suffered chronic pain and brain injury as a result.

And even though Copperfield claimed revealing the secret behind his “Lucky #13” trick would harm him financially, the judge had a care factor of approximately zero.

According to Copperfield, the trick involves him randomly selecting 13 audience members, calling them up onto the stage, and then making them ‘disappear’.

When they reappear, they are all standing at the back of the room. Magic.

What the audience doesn’t see though, is that after the curtain comes down on the participants, stagehands hurry them through secret passageways underneath the MGM Resort in Las Vegas.

They then leave the building, and re-emerge at the back of the theatre.

It was while being rushed through these passageways that Cox suffered a fall and was taken to hospital.

Cox claims he has spent over $518,000 on medical bills so far, and is seeking compensation.

The trial is ongoing.

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