A road movie about three persons traveling in a campervan on their way to Tokyo, Hamamatsu, and Kyoto. The film is based on the story of the heroine, a young girl named Momo, who was a member of the "21 Faces of Kaijin" gang involved in the Glico Morinaga Incident, and the film's ideas are remarkable, including the use of a tape recording of the actual incident.

Set primarily before the events of Kamen Rider W Forever, Kamen Rider Eternal tells the story of Daido Katsumi, the formation of NEVER, the mission that led them to target Fuuto, and reveals just how Daido obtained his Lost Driver and got his first taste of the power of Kamen Rider Eternal. As a mysterious woman retells this story to Phillip and Shotaro, they realize that Daido may not have been the simple monster he first appeared to be…

The film is divided into two chapters, "First Love" and "Endless Love", in which the author, Yoko Oguchi, chases after a different man, each saying "I love you! and chases after another man. In the second chapter, she screams in public, has sex with a man, shaves her hair and gets (really) yelled at by her parents. Beyond the fictionality and perfection of the drama, the author's daring and daredevil performance have a strong impact on the viewer.

After witnessing a strange explosion, Shinnosuke Tomari is later visited by a young man claiming to be his son Eiji Tomari from the year 2035. Eiji warns Shinnosuke that a year from now, Mr. Belt's AI will go berserk and lead to the Roidmudes overtaking humanity. However, Shinnosuke cannot immediately deal with this new information when the evil Kamen Rider Dark Drive also comes from the future, causing enough mayhem that leads to Shinnosuke being framed for it and becoming the public's most wanted.

Misa Kuroi continues her search for the demon Ezekiel and investigates a strange situation involving a wheelchair-bound doll maker named Ryo.