Throughout the 1990s and 2000s, Bell appeared in supporting roles in a number of films and television shows, including The Firm (1993), Unabomber: The True Story (1996), Walker, Texas Ranger (1998), The Sopranos (2001), and 24 (2003).

The film was a box office success, and Bell went on to portray the character in eight of the nine sequels: Saw II (2005), Saw III (2006), Saw IV (2007), Saw V (2008), Saw VI (2009), Saw 3D (2010), Jigsaw (2017), and Saw X (2023).

[1][2][3] His English mother, Eileen Julia (née Bell) Tobin, who also had Irish ancestry, was an actress who worked at the Quincy Repertory Company.

[4] His American father, Joseph H. Tobin, built and established the radio station WJDA in Quincy, Massachusetts, in 1947 and once ran for mayor of Gloversville, New York.

[5] He credits hearing a seminar by Hume Cronyn and Jessica Tandy at Boston University with inspiring him to begin an acting career.

[7][8][9] Bell played background roles in the late 1970s and early 1980s in over 30 films, including Woody Allen's Manhattan (1979), while also performing on off-Broadway and off-off-Broadway.

He recollected it being a "great opportunity" watching Sidney Lumet and Paul Newman, while also learning the technical aspect of acting.

[13] For every role he plays, starting with the initial reading of the script to the final shot of a production, he keeps a journal of various questions about and motivations for his character.

"[12] Bell moved to Los Angeles and was cast in his first feature film, Mississippi Burning in 1988, as "tough and street smart" FBI agent Stokes.

The film is about John Kramer who is an engineer-turned-serial killer that wants others to appreciate the value of life by placing them in twisted "games" of physical and psychological torture.

[17] The following year, Bell starred in Saw II, which he said was because "the character of John Kramer was not fully defined and he had an opportunity as an actor to take him to the next level".

[11] It premiered at South by Southwest in March 2015 to positive reviews with Variety pointing out the "creepy gravitas" with which Bell portrayed the role.

[37] In March 2016, Bell joined the soap opera Days of Our Lives for a five-episode arc playing Yo Ling, who is revealed to be John Black's long lost father.

Bell guest starred in a September 2019 episode of Creepshow, alongside Giancarlo Esposito in the segment "Gray Matter" that is based on King's short story.

The series is about a string of unsolved crimes committed by a group of teens in the 1990s while an investigative journalist uncovers a supernatural cover-up that is tied to her past.

[52] He has coached a Little League Baseball team and flag football, with other hobbies including hiking and playing guitar.