While watching Melissa's latest performance, Sokichi meets her seedy manager Kozo Yaguchi before Melissa's stalker, the Spider Dopant, attacks. She finds herself witnessing a memory from Sokichi wherein he was working a case involving opera singer, Melissa, and an inhuman stalker. Demanding to know why he became a Kamen Rider, the Pteranodon Yummy returns and uses the Memory Gaia Memory on her. After the Yummy escapes, a tearful Akiko threatens to call off the wedding, but reveals she is upset because her deceased father, Sokichi Narumi, is unable to attend. While confronting the male Pteranodon Yummy, Kamen Rider W receives aid from Ryu Terui, who is forced to fight without his Rider equipment due to his bride-to-be Akiko Narumi, who wants her friends to focus on her wedding. Movie War Core opened at number 1 in Japanese box offices in its first weekend, unseating Harry Potter and the Deathly Hallows – Part 1 from its two-week position. The final segment sees the casts of the two TV series come together to fight the mosntrous Kamen Rider Core when he threatens to destroy the world. After being forced into becoming a mindless Greeed, Eiji must stop Nobunaga before it is too late. However, Nobunaga attempts to resume his conquest of Japan while targeting the descendants of those responsible for his downfall.

He runs from the Kougami Foundation and into Eiji Hino's care. The Kamen Rider OOO segment of the film, written by Toshiki Inoue, sees the Kougami Foundation discovering the mummified remains of Oda Nobunaga and creating a Cell Medal-based homunculus of the man with his memories.

The Kamen Rider W segment of the film, written by Riku Sanjo, takes place after the series epilogue and features Akiko Narumi preparing for and contemplating canceling her wedding when her Kamen Rider friends become distracted by the Pteranodon Yummy ( プテラノドンヤミー, Puteranodon Yamī) after it acquires the Memory Gaia Memory and uses it to show her how her father, Sokichi Narumi, became Kamen Rider Skull. Similarly to Kamen Rider × Kamen Rider W & Decade: Movie War 2010, Movie War Core is split into three parts. Originally announced in a teaser at the end of the film Kamen Rider W Forever: A to Z/The Gaia Memories of Fate, Movie War Core was released in Japan on December 18, 2010. Kamen Rider × Kamen Rider OOO & W Featuring Skull: Movie War Core ( 劇場版仮面ライダー×仮面ライダーオーズ&ダブル feat.スカル MOVIE大戦CORE, Gekijōban Kamen Raidā × Kamen Raidā Ōzu Ando Daburu Fīcharingu Sukaru Mūbī Taisen Koa) is a 2010 tokusatsu drama crossover film in the Kamen Rider franchise that features the casts and characters of Kamen Rider W and Kamen Rider OOO.

Kamen rider ooo wiki