Cowboys &amp; Aliens, Jon Favreau, 118 mins (12A)<br/>The Inbetweeners, Ben Palmer, 96 mins (15)<br/>In a Better World, Susanne Bier, 119 mins (15)

There are five screenwriters credited with the script of Cowboys & Aliens, and by the end of the film I wondered whether they'd deliberately sabotaged each other's work – whether each time one of them came up with a good idea, the remaining four went out of their way to ruin it.

Take the two leading men, for instance. One of them is Daniel Craig as an amnesiac gunslinger who rides into a New Mexico frontier town in 1875. The other is Harrison Ford as the feared cattle baron who rules the roost. When UFOs swoop down, you'd hope to see these two action heroes going side by side into battle, striking sparks off each other before reaching a grudging mutual respect. But in fact Ford is very much a supporting player, with little more to do than Sam Rockwell's saloon keeper or Olivia Wilde's mysterious love interest. And when Ford does get his turn on screen, Craig is usually elsewhere. It's weird. Why put James Bond and Indiana Jones in the same film if you're not going to let them interact?

Craig's amnesia is wasted, too – his identity is revealed by a Wanted poster in the opening scenes – while the notion that the cowboys and aliens might have similarly rapacious natures is dangled before us and then whipped away before it's made any kind of satirical point. Beyond all of that, though, the most criminal bit of idea-squandering is the application of an irresistibly trashy title to a film that takes itself tediously seriously. Cowboys & Aliens is, let's face it, silly stuff: it's got a horse that can keep pace with a supersonic rocket, and some bug-eyed monsters who are sporting enough to use almost none of their hi-tech weaponry when they're fighting humans. And yet it trots wearily through the desert with none of the verve or levity that such silliness is crying out for. If any of the writers dreamt up a clever plot, or some decent jokes, or even a point to the whole exercise, the other four did a ruthless job of getting rid of it.

The Inbetweeners Movie transfers Channel 4's excellent sixth-former sitcom to the big screen in time-honoured fashion by packing the cast off on a foreign holiday. But aside from the location, it keeps to the tone and the look of the TV series – and that's both the best and worst thing about it. Resisting the temptation to have one of the characters being mistaken for an international drug smuggler, or to chuck in a cameo by Pixie Lott, it simply has snobbish Will (Simon Bird), sensitive Simon (Joe Thomas), loud-mouthed Jay (James Buckley) and dim-witted Neil (Blake Harrison) being their usual hopeless selves in a Greek resort rather than a suburban secondary school.

Like the series, it's an acutely observed, sweet-natured portrait of teenage friendship and middle-class British callowness. And like the series, it's fabulously rude and crude. But it isn't a stand-alone "movie", whatever the title might claim. It's really a movie-length episode which could just as well have been on Channel 4 on a Sunday evening, and which probably will be very soon.

The winner of 2011's Best Foreign Film Oscar, In a Better World, is a deliciously pungent study of escalating violence ... for a while, anyway. At its centre are a boy who fights back against a school bully, and his friend's father, who turns the other cheek when a stranger slaps him in the face. Susanne Bier's social drama boldly admits that the situation has its complications, only to iron those complications out in time for the disappointingly neat and tidy ending.

Next Week:

Nicholas Barber sees whether smash-hit novel One Day, by David Nicholls, is likely to become a smash-hit film for Anne Hathaway and Jim Sturgess

Also Showing: 21/08/2011

Glee: The 3D Concert Movie (84 mins, PG)

What a rip-off. This underwhelming selection of song-and-dance routines from the hit TV series may be staged in a vast arena, but the rudimentary choreography and off-the-peg clothing stick rather too closely to the conceit that it's just a school drama club's end-of-term show. The 3D does nothing except bump up the ticket price, and the skimpy running time would be even shorter if the songs weren't interspersed with documentary profiles of gushing, merchandise-clad fans.

Villain (140 mins, 15)

When a young woman's body is found, everyone affected by the killing – including the killer – adjusts in their own way. This bleak, ponderous Japanese melodrama takes a long, long time to reach the less than stunning conclusion that someone can commit murder in a moment of madness without being an inhuman fiend.

Spy Kids: All the Time in the World in 4D (90 mins, PG)

Robert Rodriguez revives his Spy Kids franchise with two new children, but the same old clutter of cheapo effects, Dali-esque imagery, incomprehensible plotting and lectures on the importance of family. The whiff of diminishing returns is, in this case, genuine: viewers are handed scratch'n'sniff "Aroma-scope" cards.

Kind Hearts and Coronets (101 mins, U)

The jewel in the Ealing Studios crown, this glittering black comedy stars Dennis Price as an unfailingly debonair serial killer and Alec Guinness as his eight aristocratic victims.