Ko (also transcribed Kou and Koh) Shibasaki debuted in 2000, when she portrayed Mitsuko Souma in Battle Royale. Shibasaki also won critical acclaim for her role as Tsubaki Sakurai in the 2001 film Go, which earned her several awards, including the Best Supporting Actress Award of Japanese Academy, the Hōchi Movie Award, and the Kinema Junpō Award.