Author Irvine Welsh has described James McAvoy's performance in his latest film as "absolutely amazing."
The film, which is adapted from Irvine's bestselling novel of the same name, sees the Scottish star play a drug-addicted and misogynistic detective sergeant named Bruce Robertson.
Irvine, who also penned Trainspotting, added that: "It's just one of the greatest acting performances I have ever seen, I think he's better than Robert De Niro in Taxi Driver. He is absolutely electric and is right into the character. It's a fantastic emotional performance."
Filth, directed by Jon S Baird, also stars Jamie Bell, Alan Cumming, Jim Broadbent, Imogen Poots and Downton Abbey's Joanne Froggatt.
Whilst Irvine is currently promoting the DVD release of Ecstacy, Filth is set to be released in 2013.
Photo: © Rex