Media playback is unsupported on your device Media caption Ricky Gervais: "It's a 55-year-old sales rep trying to be a rock star, it's already sad and funny"

Ricky Gervais's feature film outing as David Brent has received mixed reviews following Wednesday's world premiere.

Titled Life on the Road, the movie, unveiled in London, is a spin-off from the hit BBC TV series The Office.

While some critics thought it "excruciatingly brilliant", others judged it a "slowly unfolding disappointment".

The movie sees the former office manager now selling cleaning products but dreaming he is a rock star.

He decides to pursue his goal of stardom by touring with his self-funded band Foregone Conclusion.

As part of the movie's launch, Gervais performed on a makeshift stage in Leicester Square as his smarmy alter ego with his fake band.

The film is released in UK cinemas on 19 August. Here is a selection of the critics' opinions:

Robbie Collin - the Daily Telegraph (4*)

"If Gervais was working with more resources here than he was 13 years ago, there's zero evidence of it on screen. Happily, what's in no short supply is the same mix of uproarious failure and sledgehammer pathos that Brent at his best was always all about."

Image copyright Getty Images Image caption Ricky Gervais has produced Life on the Road as a solo venture

Sean O'Grady - The Independent (4*)

"If you have missed Brent, more or less absent from our screens in the 12 years since the last episode of the original The Office series was run, then you will be pleased to learn that he is back, and more grotesque, more embarrassing, and more humiliated by life than ever."

Henry Barnes - The Guardian (2*)

"It's clear from early on that this is a Ricky Gervais solo outing. The moderating influence of his Office co-creator Stephen Merchant (not involved - something about 'schedules') is missing, leaving a patchy comedy that lacks discipline. The mockumentary format, used so brilliantly in the original show, goes for a wander once the action gets going."

Image copyright Mary Evans Picture Library Image caption The Office, which ran on TV from 2001-03, was set in a fictional paper company

David Edwards - Daily Mirror (5*)

"Hilarious, horrifying and even heartbreaking - Ricky Gervais has made a movie that is somehow unmissable and often unwatchable at the same time... Not since Sacha Baron Cohen's Borat 10 years ago has there been a mockumentary that is so appalling funny."

Brian Viner - Daily Mail (2*)

"Alas, this big-screen 'mockumentary' sequel, written and directed by Gervais alone, is a slowly-unfolding disappointment. Comic characters conceived for TV very often misfire in the cinema, but there's an even more worrying development here as the line between Gervais and his embarrassing alter ego, Brent, becomes blurred."

Stephen Dalton - Hollywood Reporter

"This time around, Gervais is sole writer, director and star, and keeps the focus firmly on himself... Consequently, much of Life on the Road feels like the debut solo album by the lead singer of a once successful band, who is now surrounded by paid session musicians unwilling to challenge the boss over his substandard, self-indulgent coasting.

"David Brent remains an enduring comic grotesque, but this sporadically amusing big-screen resurrection is more cash-in reunion tour than killer comeback album."

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