While several citizens playing at the neighbourhood, a strange Roidmude throws a Neo Spider Viral Core.
At the Kuruma Driving License Centre, Rinna introduced the Ride Booster Set that would be useful for all three Kamen Riders. Go however finds it irritating to count Chase as their ally, earning a slap from Kiriko. As Go left them with Kiriko in remorse, Genpachiro called them that the First Division wanted the cooperation with Special Investigation Unit. Yoriko Soma tried to called for the Unit's help but find Go instead and call for his help that his little brother had been kidnapped by a Roidmude. During the meeting, it was reported that 37 citizens of Yumemigayama Village had been injured from serious attack and Mitsuhide Nira decided to hand over the case to Shinnosuke, being the son of the late officer Eisuke. They were even introduced to Noumi, whom obviously to Kiriko and Shinnosuke is none other than Brain in disguise.
Yoriko told Go of her brother's background as a real estate agent of a town while he secretly relate it to his relationship with Kiriko. Go decided to take the case on his own and promise to save the woman's little brother. At outside, Shinnosuke as Drive tried to force Brain Roidmude to reveal all of the secrets of 001. Though Brain only reveal several small details, however, he quickly take this as an opening to frame Drive. While Brain express his success to 001/Makage, an officer entered his office and demanded answer of a recent monster attack but 001 altered his memory to thought this as an accident. Shinnosuke was suspended from being Drive and the Tridoron has been towed away. While Shinnosuke decided to quit as an officer, Jun hold him off, telling that his father would died in vain. Go and the woman realised that recent cases of household areas being attacked are related to his brother's disappearances.
The Unit founded it's real estate agent, Ryo Soma, and both Gen and Rinna pose themselves as new neighbours with Shift Colorful Commercial covers Shinnosuke's disappearances while Shinnosuke went undercover quietly. Shinnosuke even bumped into the similarly undercover Go and Yoriko, while noticing the woman's relation to Ryo and Kiriko visited Chase, having required his help and him as well wanted the Shift Speed Prototype to be fixed in hopes of recovering his lost memory. Suddenly, some of the residents turned wild, with Genpachiro as well being hold off by Shinnosuke and realised a logo on his hand, as well as those affected. The true culprit appeared, Seeker Roidmude, whose true motif is to amplify humanity's negative emotions to find the one worthy of fusing with him. After Seeker knocked the affected victims for deeming the unworthy, an angry Go transformed into Mach.
While fighting Seeker, two other Roidmudes showed up and assist him in fighting Mach. As he about to be finished, the Ride Booster Set appeared and saved him. Mr. Belt ordered Shinnosuke to transform but hesitated after remembering Jun's words. Chase appeared and allow himself to take over for Shinnosuke, transforming into Chaser and and defeated the two Low Classes with Shingou Ax. However, Mach furiously attacked Chase, where Seeker revealed that it was all a part of the plan and leaves. As an untransformed Chase is about to be killed, Shinnosuke stepped in and stopped Mach. As Chase leaves and the injured citizens being carried by several paramedics, Go tearfully revealed that his motive for destroying Roidmudes is because they were his father's creation, and many people died in the Global Freeze because of his mistake. He desired to destroy them to atone for what his father had done.
- Actually a Doombot: The Special Unit fools Nira into believing that Shinnosuke has fallen into another bout of depression and lazing around in the HQ, when in reality it was a hologram made by Colorful Commercial. The real one went incognito to continue the investigation.
- All According to Plan: Seeker Roidmude says this when Mach attacks Chaser in a frenzy.
- Hate Plague: Seeker uses Neo Viral Cores to find suitable candidates to become hybrid evolutions among the general populace. This results in amplifying their negative emotions, which in turn causes entire families to go berserk on each other.
- Imagine Spot: After introducing the Ride Boosters, Rinna imagines the three Riders flying off into the battle on the Tridoron.
- My God, What Have I Done?: Both Kiriko and Gou have this reaction after a heated argument over Chase went really sour.
- The Reveal: Dr. Banno is the Shijima siblings' father.
- Police Brutality Gambit: After revealing himself as the adviser to the 1st Division, Brain fights Shinnosuke in his Roidmude form, taunting him with information about his father's death. Just when Drive had him on the rope, he transformed back to his human disguise, just as members of the 1st came to check what was going on. Brain called them for help, saying that the Kamen Rider went and attacked him for no good reason. This results in Shinnosuke getting suspended.
- Screw the Rules, I'm Doing What's Right!: Subverted at the last second. Shinnosuke was this close to disobey his suspension, which would cost him his job, saying that his duties as Kamen Rider are more important than his duties as a police detective. The Chief however manages to talk him down by saying that it would make his father cry if he would abandon the officer's pride.
- Turn in Your Badge: Due to Brain's machinations mentioned above, Shinnosuke is suspended, with not only takes him of the case, but also prohibits him from transforming into Drive at all.
- Undercover as Lovers: Genpachirou and Rinna go undercover as newlyweds moving into a new house in order to figure out how Seeker manages to make his victims go berserk.
- The Roidmude Count: 64The Answer: In a desperate attempt to undo his father's mistake of creating the Roidmudes.
