Fuuto Pi is one of the season's most anticipated anime series. And its premier event at Anime Expo didn't disappoint, winning over long-time Kamen Rider fans and newcomers alike. Based on the Fuuto Pi manga written by Riku Sanjo and illustrated by Masaki Sato, Fuuto Pi is a sequel to the Kamen Rider W series. However, the show is hard to watch in America, meaning those new to the franchise may struggle to dive into Fuuto Pi. So here is everything you need to know before starting the Summer 2022 release.

Kamen Rider W originally hit screens in 2009. It was the 10th series of the rebooted Kamen Rider franchise, which started in 2000. Viewers first saw Kamen Rider Double in the movie Kamen Rider Decade: All Riders vs. Dai-Shocker, where he made a cameo appearance to tease the upcoming show.

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The main Kamen Rider W series is set in the city of Fuuto. However, Museum, a shadowy group run by the Sonozaki Family, operates a thriving criminal enterprise. They give criminals Gaia Memories, USB-like devices that can be absorbed or inserted into tattoo-like marks called Living Connectors. Anyone who does this transforms into a monstrous creature called a Dopant. But, this has many terrible long-term effects as the Memory corrupts the user's mind.

The series begins by showing Sokichi Narumi -- Kamen Rider Skull -- rescuing a boy from a strange machine while Shotaro Hidari watches on. However, Sokichi is killed, and Shotaro and the young boy (named Philip) use a box of Gaia Memories to transform into Kamen Rider Double. This event, called "Begins Night", is frequently seen in flashbacks during the series and further expanded on in the Movie War 2010 and Movie War Core films.

Shotaro continues to work for the Narumi Detective Agency, the agency previously owned by Sokichi. However, Sokichi's daughter and the agency's new owner, Akiko Narumi, moves in and attempts to turn the agency around. She quickly learns that Philip has no memory of his past. However, he can access a mental space called the Gaia Library, a treasure trove of all human knowledge that helps Shotaro solve cases.

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Shotaro and Philip have another powerful tool at their disposal: The Doubledriver. By placing two purified Gaia memories in the Doubledriver, the pair become Kamen Rider Double. While the driver removes the harmful effects of the Gaia Memories, Shotaro and Philip share a body while transformed. Each side of the Double suit reflects the Memory currently used on that side of the driver, with Double's most famous form, CycloneJoker, being green and black.

As the story continues, Double gets other forms with unique powers, including LunaTrigger, HeatMetal, and FangJoker. Eventually, a special Gaia memory called the Xtreme Memory allows Shotaro and Philip to assume Double's final form, CycloneJokerXtreme. This gets further upgraded in the movie A to Z/The Gaia Memories of Fate, where Fuuto's wind and the hope of its civilians transform Double into CycloneJokerGoldXtreme. Double can also use any of these Memories to perform a finishing move called a Maximum Drive. This move can force a Gaia Memory out of a Dopant and destroy the rampaging creature.

As Double attempts to stop the Dopant crime wave, they meet Ryu Terui, a police officer trying to track down the person who murdered his family. He uses the Accel Driver to turn into Kamen Rider Accel. Accel is advised by a mysterious woman named Shroud, who has her own hidden agenda. However, it is soon revealed that Philip is the son of the Sonozaki Family's leader, and Shroud is Philip's mother. Shroud left the family to seek revenge for their betrayal and is working on a plan to bring them down.

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Just before Double fights the Sonozaki Family, it is revealed that a young Philip fell into the True Gaia Memory under the Sonozaki mansion, only to be revived as a data-form avatar of the True Gaia Memory. Before he was rescued, the Sonozaki Family had been using Philip to produce new Gaia Memories, hoping to use the data gathered by the Dopants to cause Gaia Impact. An event where all humans would become avatars like Philip.

After winning the final fight, Philip is absorbed into the Earth due to the Sonozaki Family's failed attempt to trigger Gaia Impact. He leaves behind a LostDriver, which only needs a single Gaia Memory. This lets Shotaro transform into Kamen Rider Joker and continue to protect the city. However, in the final episode, Philip gets resurrected in a new body. And the pair head out to defend Fuuto again.

This wasn't the end for Double. The character would appear in many crossover movies, which saw Double fight alongside other Kamen Riders. Some movies, like Movie War Mega Max, would heavily feature Foundation X, the evil organization that funded Museum, and many other Kamen Rider villains, hoping to use the data they gathered to fulfill their world domination plans.

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In 2011, a series of V-Cinema specials was launched called Kamen Rider W Returns. One focuses on Kamen Rider Eternal, the villain from the A to Z/The Gaia Memories of Fate movie. While the other follows Kamen Rider Accel as he tackles a new crime wave while navigating being married to Akiko Narumi. Fuuto Pi is set a short while after this special, though some timeline details are changed slightly.

Double would also appear in other non-canon and alternative universe crossover movies, including a role in the grand conclusion to the Heisei era, Kamen Rider Heisei Generations FOREVER. Additionally, Accel would make several other cameos in later spin-offs, including Kamen Rider Drive Saga: Kamen Rider Chaser, Kamen Rider Zi-O NEXT TIME: Geiz, Majesty, and recently 2022's Kamen Rider Revice: The Mystery. During this crossover, shots of Philip and Shotaro are shown when a character notes that Accel isn't with his friends from Fuuto, a not-so-subtle promotion for Fuuto Pi.

Kamen Rider W is among the most enduring Kamen Rider series in history, and it's easy to see why. The city of Fuuto is memorable, and Shotaro and Philip’s relationship is a fantastic take on the classic buddy-cop dynamic. This dynamic is maintained and developed even further during the Fuuto Pi manga. Hopefully, the anime can capture this essence and introduce a whole new audience to the half-boiled detective and the two-in-one Kamen Rider, even if they've not seen the original show.

Crunchyroll will begin streaming Fuuto Pi on July 31.