Born in Detroit, Michigan, Marshall moved with his family to the North West Frontier Province of Pakistan where he was raised in the city of Peshawar until the 1971 Indo-Pakistani war. He and his family then relocated to the United States.
Marshall studied Acting at R.A.D.A. (The Royal Academy of Dramatic Art, in London, England.)
- Lentz, Harris M. (2001). Science Fiction, Horror & Fantasy Film and Television Credits: Television shows. McFarland. p. 1777. ISBN 978-0-7864-0952-5. Retrieved 9 June 2011.
- Jenkins, Jeffrey Eric (2009-08-15). The Best Plays Theater Yearbook 2007-2008. Limelight Editions. p. 404. ISBN 978-0-87910-366-8. Retrieved 9 June 2011.
- Morley, Sheridan (2 May 2001). "LONDON THEATER : 'Odd Couple':The Female Version". New York Times. Retrieved 9 June 2011.