After five auditions for the role, the actor was eventually cast in August 2007. The film's producer found the original choice for the lead role, Ruslaan Mumtaz, too good-looking for the role. Boyle said, "I wanted a guy who didn't look like a potential hero; I wanted him to earn that in the film." To prepare for the role, Patel went along with Boyle while scouting for filming locations, where he was able to observe the Dharavi slums for himself. He also worked at a call centre for a day and in a hotel, where he washed dishes.