Returner

After an alien invasion threatens to annihilate the human race, a young girl named Milly (Anne Suzuki) must go back in time, and enlist the reluctant aid of skilled gunman Miyamoto (Takeshi Kaneshiro) to discover and prevent the start of the war. However trouble ensues when the two protagonists are forced to deal with a Japanese mafia boss named Mizoguchi (Goro Kishitani) who is somehow involved in the start of the war, all the while racing to find a way to stop the oncoming destruction. (official distributor synopsis)