A comedy about a wild pub crawl

The World's End scores in unexpected ways.

One shudders to think what The World's End might have been. Had the movie been made by anyone other than Edgar Wright -- the director of a trilogy of movies that began with Shaun of the Dead (2004) and continued with Hot Fuzz (2007) -- it probably would have been a kind of British knock-off of the Hangover movies, a comedy that attempted to max-out on sleaze and grossness.

Consider the plot: Wildly irresponsible Gary King (Simon Pegg) encourages five reluctant buddies to reunite to finish a pub crawl they began when they were young men eager to escape the confines of their hometown of Newton Haven, a northern English town with a generic look and no discernible distinctions.

For a time, it does seem as if Wright and his cohorts (a list that includes Nick Frost, Paddy Considine, Martin Freeman and Eddie Marsan) plan to follow a fairly standard comedy map.

We know, for example, that Frost's Andy, who seems to have buttoned-down his life, will eventually loosen up and abandon his teetotalling ways. But Wright, who wrote the screenplay for The World's End with Pegg, has a stranger, sillier and much more creative movie in mind.

Suffice it to say that the screenplay adds a wild sci-fi twist when the former high-school buddies discover that their hometown has been invaded by aliens who have turned most of the population into robots.

Once this twist has been revealed, the movie becomes increasingly crazier and a lot more inventive, employing some witty and well-executed special effects and adding an appearance by Rosamund Pike, as the sister of one of the men and a love interest for two of them. A game Pierce Brosnan appears in an extended cameo as one of the boys' former teachers.

The World's End, by the way, is the entirely appropriate name of the bar where the pup crawl is supposed to conclude.

As chief instigator, Pegg provides the movie with its centerpiece, sustaining a performance that's at once crazed, gleeful and desperate: The rest of the crew keeps pace.

No point revealing the jokes, but they are plentiful and mostly funny. Wright also manages to infuse the comedy with a sense of abandon without losing control of his movie.

Neat trick: The World's End has just enough trenchancy to keep it from being lost in its own silliness and just enough silliness to keep us from having to take any of it too seriously.