
He begins traveling through the worlds with his friend Natsumi and her grandfather. He then learns that he needs to save the World of Natsumi by traveling to the nine AR worlds, meaning other rider worlds or alternate reality worlds. During an attack of many different Kaijin from throughout the Heisei Kamen Rider history Tsukasa becomes Kamen Rider Decade. The story follows Tsukasa Kadoya, an amnesiac photographer in the World of Natsumi.

Tsukasa uses this twin-lens reflex camera produced by Blackbird, Fly, specially made for the series in color described as "Decade Low Pink". Photography is an overarching motif in Kamen Rider Decade.

Rounding up the cast was Kimito Totani who portrayed the thief Daiki Kaito/ Kamen Rider Diend. Ryota Murai was cast as Yusuke Onodera who is the series' version of Kamen Rider Kuuga. The world of Kamen Rider Kuuga, as well as most of the other Rider Worlds, sport several characters who have been renamed and cast with different actors. Another member of the cast was Tatsuhito Okuda as the mysterious Narutaki. Also involved were Kanna Mori as Natsumi Hikari/Kamen Rider Kivala, and Renji Ishibashi as Natsumi's grandfather Eijiro Hikari. Masahiro Inoue, who portrayed Keigo Atobe in the Prince of Tennis musicals, was cast in the lead role for Decade as Tsukasa Kadoya/Kamen Rider Decade. The Kamen Rider Decade trademark was registered by Toei on July 29, 2008. Kamen Rider Zi-O, the last Heisei era series of 2018-2019, acts as a spiritual sequel, where both Decade and Diend play prominent roles as re-occurring side characters who are directly involved in that series plotline.

It began broadcasting the week following the finale of Kamen Rider Kiva and was featured in Super Hero Time alongside the 2009 edition of the Super Sentai Series, Samurai Sentai Shinkenger and replaced by Tensou Sentai Goseiger. Decade, as its title suggests, is the tenth of the Heisei Rider special anniversary Series, having begun with Kamen Rider Kuuga in 2000. Kamen Rider Decade ( 仮面ライダーディケイド, Kamen Raidā Dikeido, Masked Rider DCD) is the title of the first installment of the 2009 editions of the long-running Kamen Rider Series of tokusatsu dramas.
