An anonymous letter is delivered to the Tokyo Metropolitan Police Department. The letter states that a criminal of a murder case will appear at the countdown party Masquerade Night that will be held at Hotel Cortesia Tokyo. Detective Kosuke Nitta must go undercover and work again at the Hotel Cortesia Tokyo. There, he meets Naomi Yamagishi, who works as a concierge. Without any information about the criminal, except that the person will be in attendance, Detective Kosuke Nitta works feverishly to find the criminal among the 500 attendees.

A former pro-baseball player finds his passion again in Keirin, a professional bicycle racing sport.

Toshiyuki and his wife, Chiyoko, run a store named “Fukunoya” in Fukuoka. They become friends with a takoyaki (octopus dumpling) stall owner named Tsuru and try to help her out, as does the rest of the kind-hearted community.

An evil ninja Rider, Kamen Rider Fuma, appears from the virtual reality world in an effort to conquer Earth! It is up to the CR Riders to use the power of virtual reality gaming to save a young girl’s life and stop the evil plans of Machina Vision CEO Johnny Maxima before the Bugster Virus infects all of humanity!

Based on the TV series from the same name, Mentai Piriri stars Hanamaru Hakata, the icon of Hakata, Fukuoka, alongside Yasuko Tomita, who both starred in the television show playing husband and wife respectively. With additional scenes not depicted in the original show.

The Game World launches an attack on the real world. In front of Kamen Rider Ex-Aid and the Uchu Sentai Kyuranger appears the "Arena of Death" where the destruction of the Earth will be decided. Trapped in this inescapable dimension, generations of Super Sentai and Kamen Riders must engage in a battle royale, an unprecedented battlefield of many puzzles connecting the real and game worlds. And then, "Those Heroes" revive... Everything is scaled up, all rules are broken! And when it seems like the real world will fall into a disaster, imagination brings forth unimaginable new heroes!