The period drama, based on Alfred de Musset's 19th century novel, sees the rock star play a libertine who falls into depression after his mistress betrays him. Early reviews of the film, which also stars Charlotte Gainsbourg, criticised Doherty's performances and described the film itself as "catastrophic".
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The Guardian claimed that the initial reaction to the drama was "not good", while Screen Daily's Lee Marshall said Doherty delivered "a wooden performance" in "a turgid adaptation".
"With a more or less permanently bored expression, Doherty looks like he'd rather be somewhere else; he only really comes alive in a few passages of what look like improvised laddish dialogue," Marshall wrote.
"If the intention was to play on Doherty's notoriously chaotic lifestyle in casting him as a libertine (also playing on the name of his former group, The Libertines) the effect is to show him up as a rather timid schoolboy."
Cine-Vue delivered an equally harsh one-star verdict, saying: "Doherty, like a sixth former who hasn't learnt his lines for drama class, fidgets throughout Confession of a Child of the Century and seems constantly surprised when it is his cue.
"There are one or two moments of fresh charm from the controversial lead, but they obviously belong to Doherty rather than Octave (ironically, he isn't at all convincing as a libertine)."
The Evening Standard's Derek Malcolm argued that Doherty was not on the same level as his more experienced co-star Gainsbourg.
"He tries hard, and there are moments which work in the authentic de Musset manner. Otherwise, there are quiet giggles to be had," he wrote.
Geoffrey MacNab of The Independent went against the grain, saying that "tabloid bad boy Pete Doherty is perfectly cast" as Octave.
"Doherty is playing a 19th century version of himself - and he does it very well," MacNab said. "He is understated, sardonic but has a vulnerability that stops him from seeming (too) obnoxious. The problems with an uneven film are not of his making."
Confession of a Child of the Century will open in France in September, but is yet to receive a release date in the UK.
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