Ninja Assassin is a 2009 martial arts film directed by James McTeigue. The story was written by Matthew Sand, with a screenplay by J. Michael Straczynski. The film stars South Korean pop musician Rain as a disillusioned assassin looking for retribution against his former mentor, played by ninja film legend Sho Kosugi. Ninja Assassin explores political corruption, child endangerment and the impact of violence. The Wachowskis, Joel Silver, and Grant Hill produced the film for Legendary Pictures, Dark Castle Entertainment and Silver Pictures. It was distributed by Warner Bros. Pictures.

Jung Ji-hoon, better known by his stage name Rain or Bi Rain, is a South Korean singer, songwriter, dancer, actor, and record producer. Rain's musical career includes seven albums, 28 singles and numerous concert tours around the world. He achieved breakthrough success with his third Korean album, It's Raining (2004), which spawned the number one single of the same name. The album sold over 200,000 copies in South Korea and one million copies throughout Asia, and established Rain as an international star.