Bell was born in Indiana, studied design and photography at the University of Cincinnati, then moved to California, receiving MFA from the UCLA School of Theater, Film and Television in 1990. His 20-minute MFA thesis film, Radio Inside was adapted into a feature film of the same name starring Elisabeth Shue and William McNamara and released in 1994.

Bell is a visiting assistant professor for the UCLA Producers Program.

The following is a partial list of television episodes written by Bell.

The X-Files

• 6.07 "The Rain King" (writer)
• 6.16 "Alpha" (writer)
• 7.02 "The Goldberg Variation" (writer)
• 7.09 "Signs & Wonders" (writer)
• 8.10 "Salvage" (writer)

Angel

• 3.02 "That Vision Thing" (writer)
• 3.06 "Billy" (co-writer)
• 3.08 "Quickening" (writer)
• 3.14 "Couplet" (co-writer)
• 3.17 "Forgiving" (writer)
• 3.20 "A New World" (writer)
• 4.04 "Slouching Toward Bethlehem" (writer)
• 4.08 "Habeas Corpses" (writer)
• 4.12 "Calvary" (co-writer)
• 4.16 "Players" (co-writer)
• 4.19 "The Magic Bullet" (writer/director)
• 5.06 "The Cautionary Tale of Numero Cinco" (writer/director)
• 5.22 "Not Fade Away" (writer/director)

Alias

• 4.04 "Ice" (writer & director)
• 4.20 "The Descent" (writer & director)
• 5.06 "Solo" (writer & director)

Day Break

• 1.08 "What If He's Not Alone?" (writer)
• 1.12 "What If She's the Key?" (writer)

Harper's Island

• 1.02 "Crackle" (writer)
• 1.07 "Thrack, Splat, Sizzle" (writer)
• 1.12 "Sigh" (writer)