Heavy-handed and, shockingly, not particularly funny, "The World's End" is the piddling final chapter in director Edgar Wright's so-called "Three Flavours Cornetto" trilogy (following 2004's "Shaun of the Dead" and 2007's "Hot Fuzz"). If both of those previous films were cheeky satires of, respectively, zombie movies and action pictures, this one—a take-off on the apocalyptic sci-fi subgenre—gets points only for being slightly better than the similar "This Is the End," a disaster in more ways than one. Otherwise, "The World's End" gets things all wrong, its sarcastic humor more often than not limp and its play for drama tone-deaf and overbearing when a lighter touch might have made a greater impact in regards to themes about reluctantly growing up and coming to terms with guilt from the past.

It has been twenty-three years since the happiest night of Gary King's (Simon Pegg) life: a teenage pub crawl with his four best friends that made him feel freer (and drunker) than he'd ever felt before, or since. Desperate to recapture that youthful magic, he shows up in London and convinces lawyer Andy (Nick Frost), real estate agent Oliver (Martin Freeman), architect Steven (Paddy Considine), and car salesman Peter (Eddie Marsan) to return to hometown Newton Haven and conquer the dozen bars that make up the Golden Mile. All is going well—save for Andy's insistence on not drinking—until Gary heads to the loo in pub #4 and encounters a human-looking robot full of blue goo. The guys, along with Oliver's fetching younger sister Sam (Rosamund Pike), soon determine that most of the town has been overtaken by drones from outer space out to replace the free-thinking people of Earth with replicas who all think and behave alike. Gary might be in grave danger, but he is determined to reach that last watering hole he never reached all those year's before, a place called The World's End.

A title with dual meanings, "The World's End" is inferior to "Shaun of the Dead" and "Hot Fuzz," not to mention Simon Pegg's (2013's "Star Trek Into Darkness") and Nick Frost's (2011's "Attack the Block") last non-Wright team-up, 2011's more entertaining alien comedy "Paul." If comedies are basically meant to make a person have a nice time and leave with a smile, this one, co-written by Wright and Pegg, does the opposite. It doesn't take itself too seriously until it does, and when this point comes a morose aura blankets the proceedings. Aspiring no more than a few light chuckles—heading into their second bar, called The Old Familiar, they discover it looks exactly like the one they just left—the film meanders even as it inches forward. The fight set-pieces pitting the homosapiens against a circle of rampaging "blanks" get repetitive quickly, while an extended sequence where the guys must prove to each other that they are still, in fact, themselves is like a copycat of a scene from 1998's far more inspired "The Faculty." The closer the movie gets to the finale, the darker and more self-serious it gets, Gary's grievances with adulthood, his alcoholism, and an unresolved tragedy from his and Andy's past boiling over with unsophisticated mawkishness and one of those oppressive music scores that breaks out the violins to spell out to viewers exactly how they should be feeling. There was a way to properly handle these thematic plot threads while ringing true, but this one doesn't, right down to Gary's anguished cry that these pub-hopping exploits are "all I've got!"

Simon Pegg is usually quite adept at playing guys like Gary—that is, stunted man-children and narcissistic ne'er-do-wells—but if he makes for a pleasing enough protagonist, the actor goes overboard in his serious moments. Also not helping Gary's case are the crass lies he tells his friends (yes, there's a dead mother who isn't really dead). As the more responsible straight-arrow Andy, who was injured years ago in an accident the particulars of which are gradually revealed, Nick Frost continues to make for a likable wing-man to Pegg. He isn't given enough to do here, but what he does manage to achieve with so little to work with is laudable. As the reserved, henpecked Peter, Eddie Marsan (2013's "Jack the Giant Slayer") stands out among the other three friends, while Rosamund Pike (2012's "Jack Reacher") brightens up her scenes as Sam, "the one who got away" from Gary's high school days, but she frustratingly disappears too frequently.

"The World's End" is bumbling and unkempt, though there was a point in the third act where director Edgar Wright could have brought things to a close while making an absurdist comment on the typical end-of-the-planet movies. Instead, he goes on another ten minutes with a conclusion that brings to a finish these characters in a thoroughly unsatisfying way. There has been a lot of anticipation from fans of "Shaun of the Dead" and "Hot Fuzz" to see what Wright, Pegg and Frost would do next, and this capper to their very loosely related trilogy answers this query with a middling, unpolished splat that tries, and fails, to emulate the go-for-broke mix of laughs and sentimentality that made those previous pictures cult-worthy sleeper hits. A creative miscalculation full of wasted potential, mark this dour little number down as a big disappointment.