One of the awards season front-runners (boasting seven Golden Globe nominations, more than any other film), Birdman stars Michael Keaton as a washed up former star of a superhero franchise who, desperate to fight the presumption he's a has been, writes, directs and stars in his own Broadway play. It's a role tailor-made for the 63-year-old, best known for playing Batman on the big screen 25 years ago, and his meta performance is mesmerising. 

At the centre of the film Keaton's Riggan Thomson is in the midst of a mammoth meltdown. His last-ditch attempt to rescue a morsel of artistic integrity - in the form of an adaptation of Raymond Carver's short story What We Talk About When We Talk About Love - is met with a host of dramas: on-stage accidents, secret liaisons, creative disputes.

Meanwhile Riggan's seemingly disintegrating psychological state sees him constantly taunted by his one-time fictional alter ego, Birdman, whose gravely tones provide a commentary for his every move.

Birdman is a film that wins purely on its cinematic imagination. Directed by Alejandro González Iñárritu (21 Grams, Babel), it is a technical masterpiece, designed to look like one continuous tracking shot, defying formula as the camera relentlessly glides through the corridors of the labyrinthine backstage area of Broadway's St James Theatre, taking in all that goes on around it. It is accompanied by Antonio Sanchez's vigorous jazz score, played by an on-screen drummer who may or may not be a figment of Riggan's imagination.

The performances are also to be applauded. Keaton is ably assisted by a stellar supporting cast that includes Zach Galifianakis as the play's loyal producer, Naomi Watts as an emotional co-star and Amy Ryan as Riggan's caring ex-wife.

However it is Edward Norton as Mike Shiner, an infamously temperamental method actor (Keaton isn't the only example of the film going meta) cast at the eleventh hour, and Emma Stone as Riggan's sullen daughter Sam, fresh out of rehab, who really stand out. The scenes in which Keaton, Norton and Stone share the screen - whether it be Riggan and Mike butting heads, or Mike and Sam spending a quiet moment together on a balcony - are the most memorable.

In a broader sense, Birdman is about fame and prestige, and the struggles of having one exist alongside the other ("You're not an actor, you're a celebrity" scoffs icy theatre critic Lindsay Duncan after Riggan chances upon her in bar following a disastrous preview). It's a film about popular culture, riffing on current comic book movie trends (and namechecking the likes of Michael Fassbender and Robert Downey Jr) and recognising a world dictated to by viral videos, social media and celebrity gossip columns.

All this provides an exhilarating, thought-provoking and highly rewarding movie-going experience. Birdman is already one of the films of 2015.

RATING: FIVE OUT OF FIVE STARS

Birdman is out in UK cinemas tomorrow (January 1)