THEATRE is all so often about magic, and the tale of Henry Lewis and his chums certainly has a touch of magic dust about it.

A year ago he, Henry Shields and Jonathan Sayer came up with an idea for a play, The Play That Goes Wrong, and staged it in a pub in London.

The three were so skint they could only afford to pay themselves £100 a week, and the production lost money.

But then, magic happened.

The show transferred from Islington's Old Red Lion pub to the West End's Trafalgar Studio where it was seen by top London stage producer Kenny Wax, who offered the writers a deal on the spot.

As a result, that same play, or rather an improved version, is running at the King's Theatre this week and is now a hugely successful touring show.

"We were working on a improv idea," explains writer/performer Henry, "and we came up with an hour-long piece which went on at the 55-seater Old Red Lion, where it ran for three weeks.

"Then we moved to the Trafalgar Studio and it got a new audience. And we haven't looked back."

The Play That Goes Wrong is a farce, featuring The Cornley Polytechnic Drama Society, who are attempting to stage a 1920s' murder mystery.

But everything that can go wrong does, as the accident-prone am-dram gang battle on against all the odds to finish the show.

Cues are lost, lines and entrances are bungled, someone stands on the corpse's hand and the hapless body has to muffle its scream.

A mantelpiece keeps collapsing and the stage manager is still on stage when the action starts.

It's not the corpse that's been murdered - it's straight theatre.

"When we got the chance to tour the show we wrote a second act," says Henry. "Thankfully, people think it's very funny."

Henry and his London Academy of Music & Art friends formed Mischief Theatre in 2008 and developed a series of plays.

"When we started to write this one we were having so much fun because we're all aware of the mistakes that can be made in putting on a show.

"And mistakes make for laughs. Plus, when you add the seriousness of the murder mystery genre, that makes it even funnier."

The Mischief Theatre team knew instinctively how to come up with ideas for their play about theatre disaster.

They set up their operation on next to nothing and relied on luck, imagination and a bit of borrowing along the way.

"The stresses and strains of finding our own props has given a more holistic view of what the show is all about," says Henry.

"We lost money on the first run, even though we did all the marketing and the press ourselves. And with a cast of eight you really need to play larger venues to make money."

Spoofing am-dram isn't an entirely original idea. But then, is there an entirely original idea in theatre?

"You take it and do your own thing," says Henry.

"But we though it was an interesting sub genre of comedy, and it's worked out for us."

He adds: "Usually in comedy, you want it to be slick and smooth as possible. And the great thing is we can have laughs with the mistakes."

l The Play That Goes Wrong, King's Theatre, until Saturday.