You have to wonder what kind of brain can come up with the idea of mashing together two such random films as the 1986 Ozzie adventure Crocodile Dundee and the 1946 Christmas classic It’s a Wonderful Life to create a whole new musical.

If it sounds mad that’s because it is - but there’s often method in madness and this crazy combination actually works in creating a show which is hugely imaginative, funny and also heart-warming.

So here’s the premise. It’s just before Christmas and Paul Hogan, who starred in the blockbuster film Crocodile Dundee, is in his mid-eighties and feeling washed up. His body aches, he’s all alone and he feels like he’s just about had enough of life. Indeed, he says, it would have been better had he never been born.

But up in an alternative Heaven the combined forces of Babe the Sheep Pig, Lassie and Jaws are about to have a new arrival – Burt the famous croc from Crocodile Dundee who has died at the ripe old age of 90. Determined to save Hogan from himself, Babe, Lassie and Jaws dispatch Burt back to earth to convince Crocodile Dundee that he has a future.

And so, Burt takes Hogan on a series of trips back into the past – but this is a different past from the one Hogan remembers because all of these scenarios are what would have happened had he not been born.

Some of these are minor such as an alternative life for Crocodile Dundee’s female lead Linda Kozlowski when the film without Hogan is a flop, and others are major such as a third world war.

Along the way the production pays homage to countless musical theatre moments and songs as well as some movie magic with cameos from famous performers and scenes adapted from other shows.

The cast of five are hugely talented. Paul Westwood gives us a thoroughly disgruntled Hogan who begins the show as grumpy as The Grinch but gradually discovers the beauty of life. Oliver Cartwright is a truly loveable Burt who revels in the showbiz of the role and gives his all to his solos.

Thea Jo Wolfe, Tom Kiteley and Will Usherwood-Bliss zip back and forth between all the other roles at lightning speed and yet manage to make each character completely independent of each other. They also create some fantastic cameos of famous Australians and Austrians including Hugh Jackman, Kylie Minogue and Arnold Schwarzenegger.

The production features a host of impressive songs composed by Adam Gerber with some witty lyrics and smart rhymes penned by OJS Theatre manager James Edge. Directed by Lilly Butcher, It’s a Wonderful Knife is a non-stop carnival of characters and music which expertly uses the small space of the Old Joint Stock Theatre. And George P Martin’s costumes are wonderful from the detail of Burt’s dapper croc outfit, through the muscle-bound Schwarzenegger into the claw-wielding Wolverine Jackman.

However the show does run away with itself. The story is pretty much established by the interval and doesn’t have much further to go – and yet a second act lasts another hour, rambling as it searches for somewhere to take the story apart from its obvious conclusion.

So too some of the scenes are over-long with too much repetition and explanation – the team need to trust their audience a bit more to have got the message the first time round. And while the songs are fun they do also sometimes overstay their welcome.

The harsh reality is that, while it’s always hard to kill your darlings, the creative team need to take up Dundee’s famous knife and turn it on the production - snipping away a few extraneous bits here and there would massively tighten up the show and keep us hooked all the way through.

There is no doubt there is a brilliant production simmering away just beneath the surface of It’s a Wonderful Knife, it just needs a bit of ruthless editing to bring it to the boil. This is a bold new production with some great characters and catchy songs and my hope would be that with a bit of honing it could go on to be hugely successful not just in Birmingham but beyond.

Three stars

Reviewed by Diane Parkes at the Old Joint Stock Theatre, Birmingham, on Sunday 7 December.
It's A Wonderful Knife - Christmas Dundee continues to show at the venue until Tues 30 December.