Sadako vs. Kayako (貞子 vs 伽椰子, Sadako bāsasu Kayako) is a 2016 Japanese supernatural horror film directed by Kōji Shiraishi. It is a crossover of the Ju-on and Ring series. The film was first teased as an April Fools' joke on April 1, 2015, but was later confirmed on December 10 to be a real production. It was released in Japan on June 18, 2016, Indonesia on August 10 (followed by 4DX on February 15, 2017), and in North America on the streaming site Shudder on January 26, 2017. It received mixed reviews from critics.