Edgar Wright contemplates The World's End

The World's End was inspired by a pub crawl Wright attempted as a teenager

The World's End sees director Edgar Wright team up again with Simon Pegg and Nick Frost after their previous outings with Shaun of the Dead (2004) and Hot Fuzz (2007).

Pegg stars as 40-something Gary King, who drags four old schoolfriends on a nostalgic pub crawl in the small English town of Newton Haven where they grew up.

The gang's goal is to reach the final pub - The World's End - even when they discover that most of the residents are not what they seem.

The World's End is described - by fans - as the third film in the "Cornetto trilogy", because of an ice-cream in-joke that pops up in each film.

The plot was inspired by a pub crawl Wright attempted as a teenager in his home town in Somerset.

The film also nods affectionately in the direction of science-fiction classics such as Quatermass, Invasion of the Bodysnatchers and the works of John Wyndham.

As Wright explains below, the pub crawl wasn't the only event from his youth that he put on screen.

SPOILER ALERT! Do not read further if you do not wish to know some details about the plot of The World's End.

Gary King (Simon Pegg - centre) with his ex-schoolmates played by (l-r) Martin Freeman, Paddy Considine, Nick Frost and Eddie Marsan

How annoyed are you by spoilers?

It only annoys me when it's done casually. Critics should think about how the opening weekend audience might want to discover some surprises for themselves.

Is there a common theme in the 'trilogy'?

What Shaun of the Dead and Hot Fuzz and World's End do is smuggle a different movie under the guise of a zombie movie or a cop or alien invasion movie.

Even though they all have action and carnage, they are really films about growing up and taking responsibility.

The World's End is the darkest of the three films - four of the five friends have grown up and one of them is going to drag them back to their teens with the magic time machine that is alcohol.

In Shaun of the Dead it's not Shaun's fault that there's a zombie apocalypse - he just has to get through the day.

But in this movie we wanted our main character [Pegg's Gary King] to go from being a social nuisance to a galactic nuisance.

What inspired the idea of the plastic robots and the blue blood?

Blue is a very vivid colour and very unlike blood - even alien blood. Who decided that all alien blood must be green?

When I was at school I used to end every school day with fountain pen ink all over my hands and face and down my shirt.

I thought it would be a really nice image to make those five actors regress so they all look like little kids with blue ink on their hands - to me that's an image of school.

The arms and legs popping off was inspired by Action Man - anybody who had one of those toys definitely pulled the head and arms off at some point.

Robot alert: Simon Pegg in The World's End

Do you have to be a geek to enjoy this film?

Not at all. For a lot of people Shaun of the Dead was the first zombie film they'd ever seen. So in the same way it doesn't matter if you've seen Quatermass or not.

How do you see your creative partnership with Simon Pegg?

After Hot Fuzz we'd had a break because we'd both gone off to do separate movies. The World's End wasn't the easiest one to write but it felt like the most enjoyable because not only did we reunite as co-writers but the whole theme of the movie is about friends reuniting.

The first thing we did was go away for the weekend and talked about our past, school and things that happened. There was a big outpouring of memories that started to meld together.

There are some bits of the film that actually happened to me.

Such as?

In 1998 I was driving to Devon to a wedding in a friend's car and on the stereo came a song by AC/DC.

I said: "I haven't heard this in ages - didn't I put this on a tape for you?"

And he goes: "Yeah, this is it - this is the tape!"

"Where did you find that?"

"I've always had it!"

This happened in 1998 and I made a mental note to use that in the future. It pops in the film verbatim.

Does this trilogy mark the end of an era?

It would be foolish to pretend that we're 26 forever. Simon and Nick are both husbands and fathers. It would be silly to pretend that they were still stoner flatmates.

So this is a nice way of rounding this off - we've always had this theme of perpetual adolescence.

In this film all the other guys have grown up, and this other one refuses to do so because he's scared.

We like the idea that the villain of the piece is nostalgia itself.

The World's End opens in cinemas on 19 July.