Orlando Bloom is the marquee draw in Brit boxing mockumentary, but few outside his young femme fan base look likely to support the low-fat pic. Initially amusing laffer about a South London milkman who ends up fighting the world middleweight champ becomes winded way before the final bell, with only supporting turns by local comedians to sustain interest.

Orlando Bloom, the princely Paris in upcoming “Troy,” is the marquee draw in Brit boxing mockumentary “The Calcium Kid,” but few outside his young femme fan base look likely to support the low-fat pic. Initially amusing laffer about a South London milkman who ends up fighting the world middleweight champ becomes winded way before the final bell, with only supporting turns by local comedians to sustain interest. Clock this one, which went out April 30 in Blighty, as the first misfire from Working Title’s usually reliable low-budget shingle WT² (“Shaun of the Dead,” “My Little Eye,” “Billy Elliot”).

Bloom plays Jimmy Connelly, an eager-beaver young milkman in working-class Lambeth who trains part-time at the gym of manager/promoter Herbie Bush (standup comic Omid Djalili). When British middleweight champ Pete Wright (Tamer Hassan) injures himself on the eve of his fight with Yank world champ Jose Mendez (Michael Pena), desperate Herbie drafts Jimmy to take Pete’s place. As Jimmy has been drinking two pints of milk a day all his life, his bones are hard as steel, and Herbie nicknames him “The Calcium Kid” for what he bills as a “Melee on the Tele.”

The unseen docu crew, that — in one of the film’s running jokes — is always being verbally or physically abused, joins the story seven days before Jimmy’s fight, as the media frenzy mounts. So amateur that he hasn’t even fought in a ring yet, Jimmy is trained by one of Herbie’s gymrat pals, a whimsical old Irish codger called Paddy (David Kelly).

With Bloom playing Jimmy as an all-round nice guy, the comedy comes totally from the colorful supporting roles. Jimmy’s trashy mom, Pat (impressionist Ronni Ancona), bills herself as a “massage therapist” and even offers the film crew a quickie after her interview. Jimmy’s childhood buddy, Stan (Rafe Spall), is a total bum, and his father (Frank Harper) is still in stir. Herbie himself is such a tree-swinger he can’t even pronounce the word “pugilism.”

Pic’s comic celebration of British amateurism and muddling along is thrown into sharp relief as the story briefly turns its attention to Mendez, all high-octane Yank professionalism under his baleful manager, Artie Cohen (Michael Lerner). When Jimmy, reading from cue cards provided by Herbie during a press conference, threatens to send Mexican-American Mendez “back on a banana boat,” an anti-racist storm breaks out in the Brit tabloid press, and the whole country turns against the humble milkman.

Film nixes its mockumentary credentials early on by so obviously being a scripted movie, with the sheer unbelievability of the basic premise, as well as devices like Jimmy’s killer punch. That’s all well and good, but in its place there’s a lack of sufficient invention in the script by Scottish writers Raymond Friel and Derek Boyle to sustain a 90-minute movie much beyond the halfway point. Pic pales in comparison to Brit soccer mockumentary, “Mike Bassett, England Manager” (2001), which featured sharp writing plus a strong lead perf by Ricky Tomlinson.

Boyish-looking Bloom makes Jimmy likable enough, but it’s not a strong enough performance to anchor a one-joke movie. Kudos go more to the supports, especially Djalili, superb as the gross-out Herbie, plus Kelly as the blarney-full trainer and Spall as Jimmy’s terminally slacker pal.

Tech credits are OK, given the docu approach, though the penchant for fancy jump cuts by first-time helmer Alex de Rakoff (who made the vidgame “Grand Theft Auto 2″) seems misplaced in the context.

The Calcium Kid

U.K.

Production

A UIP release of a Universal Pictures, StudioCanal, Working Title presentation of a WT² production. Produced by Natascha Wharton. Executive producers, Tim Bevan, Eric Fellner. Co-producer, Richard Johns. Directed by Alex de Rakoff. Screenplay, Raymond Friel, Derek Boyle, de Rakoff.

Crew

Camera (color), David M. Dunlap; editors, Maguerite Arnold, Jon Harris; music, the Boilerhouse Boys; production designer, Joel Collins; art director, Daniel May; costume designer, Sammy Sheldon; sound (Dolby Digital), Nic Le Messurier, Brendon Nicholson; assistant director, Nick Heckstall-Smith; casting, Jina Jay. Reviewed at BAFTA, London, April 14, 2004. MPAA Rating: R. Running time: 88 MIN.

With

Jimmy Connelly - Orlando Bloom Herbie Bush - Omid Djalili Artie Cohen - Michael Lerner Jose Mendez - Michael Pena Pete Wright - Tamer Hassan Stan Parlour - Rafe Spall Clive Connelly - Frank Harper Pat Connelly - Ronni Ancona Paddy O'Flanaghan - David Kelly Angel - Billie Piper
With: Frank Bruno, Chris Eubank.
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