All casts tend to be enthusiastic about their own shows. But I have never encountered a cast who are quite as excited and energetic as the giddy bunch I met during the stage rehearsal for Little Shop of Horrors at the ADC. When I asked them to describe the show, I was greeted with genuine chorus of “Amazing! Fun! Camp! Crazy! Hilarious! Unreal! Out of this world!” So, clearly the cast are totally and utterly in love with this show? But should you be?

Little Shop of Horrors is definitely not your typical musical. Throw away any thoughts of Wicked and Les Misérables. This is on a planet of its own. The plot? Take a deep breath: an underachieving orphan works in a failing flower shop, on the aptly named Skid Row in New York. He is in love with his co-worker, only she doesn't know, because she is in a relationship with a sadistic dentist. Throw into this a greedy and grumpy shop owner, some sassy street singers, and finally, a giant speaking, singing plant from space. Oh, and I should probably mention that the plant eats people. Chopped up, whole or limb by limb.

It started life as a non-musical black and white B-movie, shot in two days on the set of another film in 1960. Turned into a musical in 1982, it was an absolute smash hit, and was one of the first successes to be produced by Cameron Mackintosh. It landed in the West End, before being remade into a cult film directed by none other than Miss Piggy (or at least the man behind her: Frank Oz). Finally reaching Broadway in 2003, it has become a favourite for people who like their theatre just a little bit wilder and weirder.

Adam Mirsky plays the geeky Seymour, whose life consists of being a slave in a flower shop, and a slave to unrequited love. “The show is actually crazy”, he tells me. “Where else do you get a loner with a psychotic alien plant for a best friend!?” Adam is more used to playing Shakespeare, and can barely contain his joy at being let loose to sing.

Choreography is by Toby Marlow, who explains that his vision is “a sheer over-the-top camp extravaganza”. Director Rebecca Vaa is equally buoyant as she explains that the show is about life and love, and Faust and flowers, and generally celebrating the craziness that musicals have to offer. “It doesn’t take itself too seriously: it sends up the idea of musicals, the oddness of people bursting into song, and the ridiculousness of the plots. But it does it fantastically.”

Musical director Joe Beighton explains with pride that this version has a bigger orchestra than the original New York production. He lists off all the extra instruments... and somewhere between the trumpets, the bass guitar and the multiple reed section I lose track of just how big a band he has assembled.

The show features the most astonishing combination of gigantic carnivorous plant puppets: having seen them being lovingly built, I really want to give away the cleverness of the surprises. But I’ve been sworn to secrecy. But apparently I can mention the bubble machines, the UV lights, the smoke machines, and the general brilliance that the lighting and design crews have put together. I get the feeling that they’re having even more fun than the cast.

Fun is definitely the key word for this show. So, if you need some fun in your life, and have always wondered what sort of voice a man-eating extraterrestrial plant has, then come along. And even if you've seen the show before, I can guarantee, this plant has a voice like none you'll have ever heard.

Little Shop of Horrors is on from 1st - 5th November at the ADC