# William Mapother

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.

## Early life, family and education

Mapother was born in Louisville, Kentucky, the son of Louisa (née Riehm) and William Reibert Mapother Sr. His father was an attorney and served as a judge in Louisville between 1967 and 1970. Mapother Jr. is a first cousin of actor Tom Cruise, whose full name is Thomas Cruise Mapother IV.

## Career

Mapother has become widely known as a character actor, and 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 Native American fighter who joins a posse to help find missing white settlers.
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.

## Filmography

| Year | Title | Role | Notes |
| 1989 | Born on the Fourth of July | Platoon Member – Vietnam | |
| 1998 | Without Limits | Bob Peters | |
| 1998 | Trickle | Josh Riddell | |
| 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 | |
| 2001 | Swordfish | Gabriel's Crew | |
| 2002 | Minority Report | Hotel Clerk | |
| 2002 | Self Storage | Graham | |
| 2003 | The Kiss | Peter | |
| 2004 | Suspect Zero | Bill Grieves | |
| 2004 | The Grudge | Matthew Williams | |
| 2005 | Lords of Dogtown | Donnie | |
| 2005 | The Zodiac | Dale Coverling | |
| 2005 | Chloe | Doctor | |
| 2006 | Ask The Dust | Bill | |
| 2006 | The Lather Effect | Jack | |
| 2006 | World Trade Center | Jason Thomas | |
| 2007 | Moola | Bob | |
| 2007 | Moving McAllister | Bob | |
| 2008 | The Burrowers | Will Parcher | |
| 2008 | Hurt | Darryl Coltrane | |
| 2010 | A Warrior's Heart | David Milligan | |
| 2011 | Another Earth | John Burroughs | |
| 2011 | Citizen Gangster | Detective Rhys | |
| 2012 | FDR: American Badass! | Dr. Ellington | |
| 2013 | Underdogs | Bill Burkett | |
| 2014 | I Origins | Darryl | |
| 2015 | The Atticus Institute | Dr. Henry West | |
| 2015 | Blackhat | Rich Donahue | |
| 2016 | Tell Me How I Die | Dr. Jerrems | |
| 2024 | Outlaw Posse | Angel | |

### Television

| Year | Title | Role | Notes |
| 2002 | CSI: Crime Scene Investigation | Douglas Sampson | Episode: "Snuff" |
| 2002 | The Pennsylvania Miners' Story | John 'Flathead' Phillippi | TV movie |
| 2002 | Touched by an Angel | Eddie | 2 episodes |
| 2003 | Law & Order: Special Victims Unit | Luke Edmunds | Episode: "Rotten" |
| 2004 | Line of Fire | Larry | 2 episodes |
| 2004 | CSI: Miami | Pete Keller | Episode: 'Lost Son" |
| 2004 | NCIS | Kyle Grayson | Episode: "See No Evil" |
| 2004–2010 | Lost | Ethan Rom | 11 episodes |
| 2005 | The Inside | Ronald Ewing | Episode: "Skin and Bone" |
| 2005 | Threshold | Gunneson | 2 episodes |
| 2004 | Crossing Jordan | Henry Bishop | Episode: "Death Goes On" |
| 2006 | Robot Chicken | Alien Bully / Leprechaun #2 | 2 episodes |
| 2007 | K-Ville | Gordon Wix | Episode: "Pilot" |
| 2007 | Viva Laughlin | Sweet Lenny Collins | Episode: "What a Whale Wants" |
| 2007 | WordGirl | Guy Rich (voice) | Episode: "The Young and the Meatless/Mr. Big's Colossal Mini-Golf" |
| 2008 | Skip Tracer | Henry Hargrove Jr. | TV movie |
| 2008 | Lost: Missing Pieces | Ethan Rom | Episode: "Jack, Meet Ethan. Ethan? Jack." |
| 2008 | Criminal Minds | Ian Corbin | Episode: "Paradise" |
| 2009 | Prison Break | FBI Agent Chris Franco | 2 episodes |
| 2010 | Human Target | Sam Fisher | Episode "Sanctuary" |
| 2010 | I Heart Vampires | William | 2 episodes |
| 2010 | Law & Order: Criminal Intent | John Silvestri | Episode: "Love on Ice" |
| 2011–2014 | The Mentalist | Richard Haibach | 4 episodes |
| 2012 | Burn Notice | Garret Hartley | Episode: "Shock Wave" |
| 2012 | Justified | Delroy Baker | 2 episodes |
| 2012 | American Horror Story | Misogynist Driver | Episode: "Dark Cousin" |
| 2013 | Mad Men | Randall Walsh | Episode: "The Flood" |
| 2013 | Castle | Carl Matthews | Episode: "The Disciple" |
| 2014 | Hawaii Five-0 | Eric Porter | Episode: "Ka Makuakaneka" |
| 2015 | Constantine | Jacob Shaw | Episode: "A Whole World Out There" |
| 2015 | Grimm | Dwight Eleazar | Episode: "The Believer" |
| 2016 | Supergirl | Rudy Jones / The Parasite | Episode: "Changing" |
| 2017 | MacGyver | Daniel Horn | Episode: "Hole Puncher" |
| 2018 | The Blacklist | Bill | Episode: "Ruin" |
| 2020 | 9-1-1: Lone Star | Bruce Ackerman | Episode: "Monster Inside" |
| 2021 | FBI Most Wanted | Travis Russel | Episode: "Winner" |

### Video games

| Year | Title | Role | Notes |
| 2010 | Fallout: New Vegas | Colonel James Hsu | |
| 2012 | Hitman: Absolution | Agent 47 | Motion capture |
| 2016 | Hitman | Dino Bosco | |