Like a happy hardcore hall of heroes - with its bright yellow, smiley face emblazoned carpet, and specially commissioned spray paint mural still in progress - the Watchmen world premiere was a trippy affair. With the entire cast in attendance and a rather less dressy audience than for your average red carpet event, we saw exactly what was under the hoods of our masked avengers.

First along was the stylishly Dorian Gray-esque thesp Matthew Goode, who takes on the role of super-brain Adrien Veidt, otherwise known as Ozymandias. Goode told us how coped with the pressure of re-enacting the most lauded comic book of all time. “It was very nerve-wracking in the beginning. But that was one of the good things about having Zack helming it - he’s a human shock absorber. He’d come in and be bouncing off the walls with energy and excitement and he’d make it really fun. In the hands of someone else I would have been a lot more scared.”

Click here for photos from the red carpet.

Shooting Watchmen straight after his turn as the social-climbing toff Charles Ryder in Brideshead Revisited, Goode expressed his surprise at having to bulk up for his part as the coiffeured caped-crusader – but said he'd revelled in the Bowie stylings (think white blonde, circa Let’s Dance) used to inspire his look : “They decided to make it look like Bowie had channeled his look from me. So I was like, 'Hmm...that could work.’”

Whilst Goode was sad to leave his bleached bonce behind, Patrick Wilson admitted that he had taken a little keepsake from his time as Nite Owl. "Well, I actually took some gloves. But nobody - well, now everybody - knows about that, because I keep talking about it!"

That’s not to say he will wear them any time soon, not fancying the idea of a bit of vigilante moonlighting: “Well the costumes pretty great, but I’m a New Yorker, and we usually keep ourselves to ourselves.”

Jackie Earle Haley, who has possibly the most all-encompassing costume in the movie, regrets not having stolen a little something from his get-up. “I didn’t take anything - and now I’m thinking damn, I should have!”

The superhero spiel was, according to Haley “a real psychopathic experience”, and rather oddly “quite nippy” (although not quite as drafty as it was for Silk Spectre, eh?); but the character-actor came to the twisted moralist Rorscharch well prepared. He staged his own adaptation of Watchmen: “I wanted this part so bad, I got the script, excised the scenes, moved them around, went and got a cheesy Halloween Rorschach costume and filmed for about half a day and sent it to Zack.” Then, Haley was also able to use his own martial arts skills to skip fight training prior to filming - unlike the other softies who “had to start from scratch and just learn how to throw punches”.

As Jeffrey Dean Morgan sauntered past, it was hard not to imagine the bear-like hunk of a man, with a freshly applied handlebar 'tache, practicing upper cuts alongside a goggled Patrick Wilson, and Malin Akerman playing hardball in her shiny fishing waders.

No such thoughts could be entertained of the exceptionally sophisticated Carla Gugino who sashayed down the yellow carpet in a nude tulle number, topped off with a crown of ozone-unfriendly, vertiginous hair. Talking about her ageing process in the film, she said: “It was fascinating. We had the most extraordinary make-up and prosthetics people on this movie, so it was very helpful for me in playing the role. It was fun to cover the forty years and span her whole life.”

Whilst Gugino and Akerman (stunning in floor length, black lace) got the flashbulbs apoppin’, the last Watchman to chat was Billy ‘Blue Hat’ Crudup - who took on the most drastic transformation in the film, as the atomic man Dr. Manhattan. Relaxed in the face of fan expectation, he said: “It would be misplaced pressure - because there’s nothing I can do now!”

And, at that, the Watchmen had to get back to some more important spectating – that is, watching themselves on the big screen. And so, Empire hit the mean streets of London’s West End for a spot of vigilante action in their absence. Watchmen hits UK cinemas on March 6.