Angus Macfadyen, a fan of certain horror films including Saw, was cast as Jeff after reading and liking the script. Costas Mandylor was cast as Forenesic Hoffman after being introduced to Bousman. Mandylor explained, "At some point I was introduced to the director and he asked if I wanted to come up and have some fun for a week on Saw III. So I thought why not, they're some good guys and all that, so were gonna have some fun. So being in that movie for a minute or two, I made the most of it and had fun with the guys". J. Larose was cast as Troy, Jigsaw's victim at the beginning of the film. Larose found challenge in playing a role that required making the character's pain look and feel authentic but felt grateful for playing the opening sequence victim of a Saw film, appreciating his opportunity to work with Bousman. Monica Potter, who played Alison, the wife of Dr. Gordon in the first film, was approached to reprise her role in the film but she declined the offer due to a lack of interest. She felt that she had done "plenty" with the first film. Similarly, Rigg's role in the movie was significantly reduced as Lyriq Bent was unavailable due to his work in Angela's Eyes (2006) at the same time; despite the filmmakers' attempts to make his schedule work, Bent was only able to shoot one day. Bent later speculated that Rigg's intended role in the film could have been that he later had in Saw IV (2007) if he had been available. Filming Saw III was given a larger budget of $10 million, compared to Saw IIs $4 million. Principal photography took place for 27 days at Toronto's Cinespace Film Studios from to late June. Production borrowed the bathroom set used in Scary Movie 4, which parodied the franchise. Almost all the transitions from one place to another were not made using digital effects; the transitions were shot on the spot. For example, when the camera moves from Troy's crime scene to Kerry being in the bathtub, Meyer had to run, take off all her clothes, and jump into the tub. Visually the film is akin to the previous two with using quick cuts and fast-paced rhythms. Bousman said, "We're using a lot of whip pans and flash frames to create a dynamic feel". Post-production