Born: April 17, 1965
Birthplace: Louisville, Kentucky, U.S.
William Reibert Mapother Jr. (/ˈmeɪpɒθər/; born April 17, 1965) is an American actor, known for his role as Ethan Rom on the television series Lost and starring in the film In the Bedroom. He is also known for the film Another Earth.Mapother was born in Louisville, Kentucky, the son of Louisa (née Riehm) and William Reibert Mapother Sr. He is of English, Irish, and German ancestry. He is a first cousin of actor Tom Cruise (whose birth name was Thomas Cruise Mapother IV). His father was an attorney, bankruptcy consultant and judge in Louisville, between 1967 and 1970; William Sr., died on June 22, 2006, after fighting lung cancer and pulmonary fibrosis.
Mapother graduated from the University of Notre Dame as an English major. Before becoming an actor, he taught grades 7-12 in L.A.U.S.D. schools in East Los Angeles for three years.
Mapother has become widely known as a character actor, who sometimes plays scary or otherwise dark characters. He played a pivotal role in Todd Field's In the Bedroom, and is perhaps best known as Ethan Rom in the TV show Lost, which he played for 11 episodes during the life of the series.
Mapother has also had considerable roles in a series of independent films, such as The Lather Effect, Moola, Hurt, and Another Earth. Mapother starred in The Burrowers as a former Native American fighter who joins a posse to help find missing white settlers, only to discover that the hunters have become the hunted.
In September 2007, he was elected to a three-year term on the National Board of Directors for the Screen Actors Guild.
He has provided the motion capture work for Agent 47, the main character in the 2012 video game Hitman: Absolution and also provided the voice before series veteran David Bateson was recast. In 2014, he played the lead in the paranormal horror film The Atticus Institute.
He is a founding partner of the film finance platform Slated.
|1989||Born on the Fourth of July||Platoon Member - Vietnam|
|1998||Without Limits||Bob Peters|
|1998||The Unknown Cyclist||By-Stander|
|1999||Magnolia||WDKK Show Director's Assistant|
|2000||Mission: Impossible 2||Wallis|
|2000||Almost Famous||Bartender||scenes deleted|
|2001||In the Bedroom||Richard Strout|
|2002||Minority Report||Hotel Clerk|
|2004||Suspect Zero||Bill Grieves|
|2004||The Grudge||Matthew Williams|
|2005||Lords of Dogtown||Donnie|
|2005||The Zodiac||Dale Coverling|
|2006||Ask The Dust||Bill|
|2006||The Lather Effect||Jack|
|2006||World Trade Center||Jason Thomas|
|2008||The Burrowers||Will Parcher|
|2010||A Warrior's Heart||David Milligan|
|2011||Another Earth||John Burroughs|
|2011||Edwin Boyd: Citizen Gangster||Detective Rhys|
|2012||FDR: American Badass||the doctor|
|2015||The Atticus Institute||Dr. Henry West|
|2016||Tell Me How I Die||Dr. Jerrems|
|2002||CSI: Crime Scene Investigation||Douglas Sampson||1 episode|
|2002||The Pennsylvania Miners' Story||John 'Flathead' Phillippi|
|2002||Touched by an Angel||Eddie||2 episodes|
|2003||Law & Order: Special Victims Unit||Luke Edmunds||1 episode|
|2004||Line of Fire||Larry||2 episodes|
|2004||CSI: Miami||Pete Keller||1 episode|
|2004||NCIS||Kyle Grayson||1 episode|
|2004-2010||Lost||Ethan Rom||11 episodes|
|2005||The Inside||Ronald Ewing||1 episode|
|2004||Crossing Jordan||Henry Bishop||1 episode|
|2006||Robot Chicken||Alien Bully / Leprechaun #2||2 episodes|
|2007||K-Ville||Gordon Wix||1 episode|
|2007||Viva Laughlin||Sweet Lenny Collins||1 episode|
|2007||WordGirl||Guy Rich (voice)||1 episode|
|2008||Skip Tracer||Henry Hargrove Jr.|
|2008||Lost: Missing Pieces||Ethan Rom||1 episode|
|2008||Criminal Minds||Ian Corbin||1 episode|
|2009||Prison Break||FBI Agent Chris Franco||2 episodes|
|2010||I Heart Vampires||William||2 episodes|
|2011-2014||The Mentalist||Richard Haibach||4 episodes|
|2012||Justified||Delroy Baker||2 episodes|
|2012||American Horror Story||Misogynist Driver||1 episode|
|2013||Mad Men||Randall Walsh||1 episode|
|2013||Castle||Carl Matthews||1 episode|
|2015||Constantine||Jacob Shaw||1 episode|
|2015||Grimm||Dwight Eleazar||"The Believer"|
|2016||Supergirl||Rudy Jones / The Parasite||1 episode|
|2017||MacGyver||Daniel Horn||1 Episode "Hole Puncher"|
|2010||Fallout: New Vegas||Colonel James Hsu|