Forget novels, forget screenplays. Film scripts are for fucking losers. These days any aspirant wordsmith worth their salt is working on a musical. I, for example, have about 200 words of Don’t Go Back To Dalston: The Razorlight Story stowed in a drawer somewhere, and I bet you, your mum and your dad and your gran have something similar on your back burner. And who can blame us all? The renaissance of the stage musical from jazz-handed school-trip trauma hell over the last few years, little to do with the Les Mis film and everything to do with the smart, self-aware, funny likes of Matilda, Avenue Q and The Book Of Mormon, means musicals are cool.

But even though everyone’s now a musical theatre fan (previously the social status equivalent of collecting scrapbook cuttings of the Queen Mum), you still probably weren’t expecting the trumpet player from Belle & Sebastian to open a show called Cannibal Women Of Mars.

Yet Mick Cooke, is doing just that at Glasgow’s Tron tonight. His story, co-written with friends Alan Wilkinson and Gordon Davidson, is set on Mars, 2113, where a race of all-female Martian flesh-eaters farm the sex-starved men of an overcrowded, socially-fucked future Earth for their own mastication.

Princesses Yasmin and Pippa are about to be intitiated into this cannibal culture by way of a man-chewing coming of age ritual. The designated victims are unemployed 21-year-olds Jaxxon McGhee and Largs Lido, who think they’ve got an easy ride because Mars girls are easy, but nearly spark a solar system-sized crisis when the princesses plump for love over grub.

I mean, it’s not exactly ‘Funny Little Frog’, is it?

Hello, Mick. So what brought this interplanetary jape on, then?

Mick Cooke: I'd been to see Avenue Q, and I was quite taken with the fact that, looking at the audience it was quite clear that a lot of the people there didn't normally go to musicals, myself included. Then in 2011, I got together a couple of writer friends, and suggested writing a musical together. We gave ourselves two weeks to come up with some different ideas, and after two weeks I just had the phrase "send more men" and the idea that it was going to be set on Mars. And Alan, one of the co-writers, suggested that the reason there was no men on Mars was that they were being eaten by a female cannibal population. The other writers, Alan and Gordy, they're kind of more the sci-fi fans and I'm... I like Star Wars, but sci-fi quite often puts me off things. So I was quite keen that we sort of downplayed the sci-fi elements. It does happen to be set in the future on Mars but it's essentially a love story. It’s a comedy and it's a love story and there's a slight horror element to it as well.

What had been your experience of stage musicals before Avenue Q? Did you see any of the big beasts when you were younger??

MC: I was actually in a school production of Grease when I was a kid, and I actually really enjoyed that. I played Doody, one of the very small characters. Probably the most insignificant character.

I can’t even remember him.

MC: No. Nobody does. But that was a great experience. We actually did four nights at the Dundee Rep. I think I kind of must have got a bit of the bug then to be honest... My wife's quite into musicals, and I love old movies, Singing In The Rain and that kind of thing, High Society. There's elements of that definitely in it. And a little bit of Gilbert and Sullivan creeps in but in the way Eric Idle would do a Gilbert and Sullivan pastiche. 'I'm An Evil Bastard', which is the President Of Earth's song, has that: [sings] “I'm an evil bastard / Everyone who knows me knows that's true / I'm an evil bastard / I do what evil bastards do”. And then it kind of goes into a hornpipe/jig-type thing in the middle. It's definitely quite Monty Python in places.

Maybe it's like... all the sort of newer musicals that are more comical, fun and self-conscious, it's almost like they've made a link back to those things that bypass the Lloyd Webber years...

MC: It is kind of going back that way, definitely, yeah, it's kind of connecting up more with the musicals and the 40s and 50s.

That was what did for the reputation of musicals, really, wasn't it? Cats and Starlight Express and stuff.

MC: Yeah, and they've been so all-consuming as well. They've just completely cornered the market for so long. I think probably the South Park guys, their love of the old American musicals has probably had an effect on lots of things. I mean, something like Avenue Q takes more from that kind of old American thing.

Were you tempted to just go with a jukebox musical?

MC: There was quite a period of jukebox musicals being sort of the norm almost. I find it quite fine to be doing something that's completely original. While we were writing the thing I got one of these books like, How To Write A Musical, written by an academic guy in America. And basically the main bit of advice at the start is, "Do not write an original story, whatever you do. You will fail." That's pretty much what it says. If that's what they try and tell people... I mean, America's got an academy dedicated to writing musical theatre and things, so if that's what they're teaching there, it's no wonder that there's not many original stories out there.”

Obviously Stuart Murdoch’s working on the film God Help The Girl at the same time, and it’s very definitely a Belle & Sebastian-style musical. Did you deliberately go as far in the other direction as possible?

MC: There's no sort of deliberate thing about it, but it's funny, I was actually speaking to Stuart the other day, and he was asking about the tone of the show and stuff, and I was saying "Stuart, it's absolutely nothing like God Help The Girl, you know?" And no offence at all, because God Help The Girl is going to be a great film, and I'm really proud to have played a part in it, but it's definitely of the Belle & Sebastian aesthetic. Because it's come from Stuart, just like the whole concept of Belle & Sebastian has basically come from Stuart... Whereas this... it probably is the opposite end of the spectrum, to be honest. The way the Tron are playing it is incredibly camp. They've got two glitter balls for the moons.

If you were a Martian cannibal, which member of Belle & Sebastian would you choose to dine upon?

MC: [laughs] Well, I wouldn't choose Beans [keyboardist Chris Geddes] because he's far too skinny. I'd probably just take a finger from each of them or something and just put it in a pot. Or it'd have to be whoever can't run fast, which is quite difficult, because there's a few runners in the band. Stevie's [Jackson, guitarist] quite slow, actually - you could probably catch Stevie quite quickly.

There’s a lot of great songs that reference Mars. What’s your favourite?

MC: It's gotta be 'Life On Mars', hasn't it, really? It is. I actually need to put together a playlist of songs to play before and during the interval.

You could also have ‘Girl From Mars’ by Ash.

MC: That's a good one actually. In fact, Ash doing that sort of modern take on the Buzzcocks, that's kind of what we were doing with 'On The Run With A Girl From Mars'. The guys going to Mars are 21. Sex has been banned on Earth, they've never had sex. So they're up on Mars, they're 21, and they think they're going to get sex. So they're basically as excited as any human could possibly be. And it's trying to kind of get that sort of exuberance across.

What are the other big influences on the songs?

MC: I'm a big fan of Flight Of The Conchords and Bill Bailey and that kind of musical comedy, and there's quite an element of that. What I love about Flight Of The Conchords is the way they do very respectful, well-executed parodies of different genres. We've got a Barry White number for one of the characters, Fat Joe, one of the guys that our two heroes meet on the Mars ferry. He likes to think he's a hit with the ladies but he really isn't, he's just a sort of disgusting human being. The cannibal women songs have a Latin thread running through them. We have an emotional, Bonnie Tyler-type rock ballad for the end of act one as well, Princess Yasmin's conflicted song. She's about to come of age, and she has to eat her first man, but she's fallen in love with him.

Sort of like a flesh-eating 'I Don't Know How To Love Him', then?

MC: It's 'I Don't Want To Eat You, I Just Want To Love You'. I mean, it's comedy, but the strange thing is particularly when it's sung by really good comic actors and singers it's done completely deadpan, and though it's a slightly ridiculous emotional situation you're actually right there with them. You can feel the conflict.

Cannibal Women Of Mars opens at the Tron Theatre, Glasgow, on Friday July 5