Cillian O'Sullivan

Actor

Cillian O'Sullivan

Born September 28, 1989 in New York, USA5 films

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The best way into Cillian O'Sullivan's work
Halo: Nightfall posterFirst watchHalo: Nightfall20146.8as Christian Ramsey (uncredited)A supporting role in one of the best-rated films of their career.Set between the events of Halo 4 and Halo 5: Guardians… Halo: Nightfall tells the dramatic story of legendary man hunter and Naval Intelligence Officer Jameson Locke and his team as they…View film

Essential films

Ranked by role, acclaim and reach
Maze poster5.8Maze2017

Filmography

5 films as actor
  1. 2025The Lost PrincessAlec Touati
  2. 2019Misty ButtonJames
  3. 2017MazeBobby
  4. 2014Halo: NightfallChristian Ramsey (uncredited)
  5. 2008Uncle Bill's BarrelTom Lynch