For me, it's anti-panto season, and nothing I've seen is further away from the fabricated joy, cheesiness and thoughtlessness of a panto than Soho Theatre's Christmas show – The Night Before Christmas by Anthony Neilson. Sure, at times it is crass and cross-dressing plays a part – but it's packed full of surprises. And that's how it should be.

The story goes like this: an elf has been caught trying to steal some warehouse paraphernalia from a lowly warehouse manager turned con-artist called Gary. Gary calls his wannabe coke-addled (as in he wants to be coke-addled) friend, Simon, along to assist and before long songs that capture the ridiculousness of the human condition are being warbled and drug-based elf excuses are made. Then, when you least expect it, in comes the manager/con-artist's occasional prostitute and constant wailer of a mother, Cherry. A classic Christmas tale you might (never) say.

Anthony Neilson writes with an audacity which takes us completely off book in terms of Christmas festivity, unless your Christmas is an attempt at oblivion, full of painful reflections, drinking and a few illegal pastimes. Well, let's face it, in some ways this isn't so far from the truth. The Scroogian Christmas songs are certainly unconventional, but then tuneless tunes fit Neilson's unlyrical lyrics. It's an off-beat style that takes a few minutes to get into and by the end the audience is left wondering whether they should laugh or pity the characters that plod the stage.

The coyly charming Navin Chowdhry takes on plucky yet mixed-up Gary. Prostitute Mum Cherry is played by Rebecca Atkinson, who takes the  audience's breath away with a ballet routine that comes out of nowhere. What a joy to see a performer with the confidence to know the intermittent and unsure tittering of an audience will soon die away as the purpose becomes apparent. Gorgeous and, as ever, surprising. Then there is Craig Kelly whose downtrodden, still-living-with-mum Simon is the most three dimensional of the characters, complete with attitude-filled exterior and sarcastic nuances. Elf, played by Craig Gazey, is the most naturalistic of the characters, believe it or not, and it's through him that Nielson spins all his incredible ideas of what Santa and his elves are really about. Imagination is another Christmas theme that is ever present in this play.

What makes this version of The Night Before Christmas worth a look and a laugh is the complete lack of sweetness, the unashamedly obscene jokes, the unapologetically modest set and sound and the joy of seeing something wholly different from the norm.

The Night Before Christmas, at Soho Theatre

Twas the Night Before Christmas, when all through the warehouse, only an elf was stirring... This is the set-up for surreal writer Anthony Neilson's characteristically original take on the conventions of Christmas shows. At the Soho Theatre.