He said: "I was going through a period where I was going down the 24-hour spas in Koreatown, where you'd go in at 2 am and have a steam or a sauna and get a really hard acupressure massage. It's a very weird sub-culture and I thought maybe Bobby Pellitt would do this."
Colin underwent a physical transformation for the film and says it was "liberating" to play such an unattractive character.
He told the Independent newspaper: "I had a very clear idea of this guy that was obsessed with all things Asian, loved karaoke and drove a Firebird – and the bald cap and the comb-over.
"I was totally creeped out when I first saw myself like that but is was also very liberating."