|Date of Birth||April 17, 1965 (age 51)|
|Origin||Louisville, Kentucky, USA|
William Mapother portrayed Ethan Rom.
- Cousin of Tom Cruise and Lee Anne De Vette.
- Graduated from Notre Dame with a B.A. in English
- Was a school teacher in East Los Angeles for 3 years before becoming an actor.
- Went to St. Xavier High School in Louisville Kentucky.
- His father, William, Sr., is an attorney and bankruptcy consultant and was a judge in Louisville, KY (1967 - 1970)
- His family's law firm has the street address of 815 W Market Street.
- Brother of Amy Mapother and Katherine Mapother
- Last name is pronounced "MAY-pah-ther"
- Attended a Church of Scientology course in 1989 but is not currently affiliated with the Church of Scientology.
- Is a graduate of the Joanne Baron/D.W. Brown Acting School in Santa Monica, California.
- Played Gunnison in CBS's cancelled series "Threshold."
- Guest starred in an NCIS episode as a kidnapper.
- Guest starred in a CSI episode.
- Appeared as an Agent in "Swordfish".
- Appears in the DVD extra "Lost in a Day" on the Lost: The Complete Third Season (DVD).
- Is a 2007-2008 member of the SAG National Board.
- Shares a birthday with L. Scott Caldwell and Henry Ian Cusick.
- William Mapother played Marine rescue worker, Thomas, who found two surviving PAPD officers in the rubble, in World Trade Center.
- Played Parcher in the 2008 western horror movie "The Burrowers", which also featured Clancy Brown and Doug Hutchison.
- Starred as Steve Hedges in the 2007 comedy "Moola", alongside Doug Hutchison.
- Recently appeared in the popular web series "I <3 Vampires" on Take 180 as the vampire William.