If Hollywood is high school with money, then the Academy Awards show is the school play. It's the one occasion when even the biggest movie stars are reduced to nervous, star-struck kids ­ getting tongue-tied, sneaking out for cigarettes and having mini spats.

Behind the scenes at the Kodak Theatre is the best reality TV show never filmed, an off-limits paradise where stardom reveals its human side.

Backstage is the only place you can find Renée Zellweger, Diane Lane and Hilary Swank lined up outside the single ladies' lavatory in 2003, waiting like mere mortals, as Julie Andrews emerges with a less than regal flush.

"Yes," said Andrews to the disbelieving laughter, "Mary Poppins really does go to the bathroom." It is where 2005 host Chris Rock bounced off stage with a happy string of expletives, only to catch Sean Penn's death stare following his jokes about his friend Jude Law's place in the Hollywood pecking order. "Sean! It was a joke, man!" And it is where Barbra Streisand and Dustin Hoffman are having last-minute thoughts about their lines as they head for the stage. "Do you know what we're supposed to be doing out there?" "No, I didn't get a script." "Neither did I." (Scripts were supposed to be couriered to them a week ago.) Getting access to this precious hinterland is the preserve of a select few.

The press corps is kept in the Renaissance Hollywood Hotel next door and even Oprah Winfrey has to confine her interviews with the winners to right by the stage.

For the past six years, Art Streiber has been the only photographer to be granted full access backstage "by the grace of the Academy", which is no mean feat. His three predecessors were dropped for what an Academy spokesman called "perceived offences against celebrity protocol". One photographer was actually ejected by security midway through the show. Another, a no-nonsense former war photographer, didn't even make it past rehearsals.

Streiber, a genial 44-year-old, is more than happy to play by the rules.

"The days when a photographer like William Claxton could hang out with Steve McQueen for days on end and get these amazing candid moments doesn't exist any more. Hollywood celebrity photos are now all controlled by publicists.

Backstage at the Oscars is the last place where you can see real, genuine reactions from big stars." Streiber was there to catch Charlize Theron, hand on forehead, "completely lose it" offstage after she won for Best Actress ­ "The enormity of it just hit her" ­ and he snapped Cameron Diaz, joking around in rehearsal with a fake Oscar between her legs.

This air of surreal intimacy only increased when the show moved to Hollywood's 3,300-seat Kodak Theatre in 2001. Despite being purpose-built for big shows, the Kodak's backstage area is minuscule compared to the old Dorothy Chandler Pavilion and Shrine Auditorium. It quickly fills up during rehearsals, which start four days in advance.

The host for the four-hour show, which this year is comedian and chatshow host Ellen DeGeneres, will roadtest their gags every day, then retreat to rewrite with their team of writers and the show's producer. Steve Martin proved the most unflappable host, even pausing for comic effect after a lighting fixture smashed down next to him; Whoopi Goldberg was the most raucous, letting fly with risqué jokes that could never be used on prime-time for a show with 600 million viewers worldwide.

"It's like running a three-ring circus with egos for elephants," says Gil Cates, producer of 13 Oscars shows. "And you have to keep it short.

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