Geoff Cox’s DVD guide:21 Jump Street, Rampart, Young Adult

Dimwit cop duo Schmidt (Jonah Hill) and Jenko (Channing Tatum) hated each other when they were at school together, but they’ve grown up to become pals.

They are forced to relive the horrors of their adolescence when their captain (Ice Cube) decides their youthful appearance makes them the perfect undercover agents posing as students to crack a high-school drug ring.

Although the original series had pretensions to drama, the set-up here is played strictly for laughs.

Buddy comedies stand or fall on the chemistry between the comic pairing. While Jonah Hill is certainly a lot of fun as the needy nerd, it’s Tatum who really shines as the jock cop who believes that arrested criminals should be informed that they “have the right to be an attorney”.

Some apt jokes about how Tatum looks far too old to be in high school are thrown in. Not that it did any harm to Depp, who pays back the favour by appearing in a cameo.

> Woody Harrelson is in top form in RAMPART (15: Studio Canal), a superb character study of a tormented LAPD cop living across two adjacent houses with his two ex-wives and daughters.

Harrelson offers a powerhouse turn as bigoted Dave Brown, a Vietnam vet and Rampart Precinct officer dedicated to doing “the people’s dirty work” and asserting his own code of justice.

It’s 1999 and a corruption investigation is in full swing, but this is just a backdrop to Brown’s meltdown after he’s caught on tape beating a suspect.

Brown starts to feel he’s a scapegoat to distract attention from the scandal that’s brewing.

What Brown doesn’t know is that he’s a man out of time and the force just wants to wash its hands of him.

As a thriller, Rampart, adapted from an original screenplay by crime writer James Ellroy, can be tough going at times, although the performances from the likes of Ned Beatty and Sigourney Weaver can’t be faulted.

It doesn’t quite match LA Confidential for complexity and scale but captures some of the grit and dynamism of the author’s hard-boiled style.

> Caustic and quirky satire YOUNG ADULT (15: Paramount) reunites director Jason Reitman with Juno writer Diablo Cody.

Charlize Theron is cast as immature teen-fiction author Mavis, who returns to her Minnesota home town, intent on luring away her now happily married high-school boyfriend (Patrick Wilson).

This odious former prom queen has no redeeming qualities and razor-sharp putdowns and Theron’s fearlessly unrestrained performance provide car-crash entertainment.

Back on her old stomping ground, the delusional Mavis’s barely hidden neuroses spew out in a barrage of amusingly monstrous banter.

This unpleasant nastiness gives the narrative bite, but the film does have a heart – provided by Mavis’s crippled former classmate and sardonic voice of reason Matt (Patton Oswalt).

He shows Mavis a warmth and kindness she really doesn’t deserve and this heroic misfit adds emotional depth to the story and personifies its moral message.

> Part psychological thriller, part full-blown horror flick, THE SQUAD (15: Momentum) is an efficient tension-builder about a group of elite Colombian soldiers sent to a remote outpost to regain contact with another unit.

They find the place littered with corpses, walls daubed with blood and strange symbols intended to ward off evil.