Waking up from a strange dream where he extracted Kamen Rider Ex-Aid’s power, Sento and Ryūga are alerted to a Smash attack and find themselves instead encountering Bugsters immune to their attacks until Sento uses the newly created Doctor and Game Fullbottles to transform into Ex-Aid. But a blue-armored figure called Kaiser appears and steals the bottles which Sento retrieves while Ryūga is thrown into a machine that sends him to a parallel world where the Skywall does not exist. Suddenly, Sento’s world shifts between dimensions and appears next to the other world, spreading hordes of Bugsters in both. With Emu unable to transform into Ex-Aid, his fellow Riders take the initiative against the Bugsters before they are confronted by the red-armored Kaiser Reverse, revealing that the Bugsters epidemic is fuel for his machine Enigma as it and its counterpart in Sento’s world seals the powers of the Gamer Drivers and Gashats. Kaiser Reverse then attempts to kill Emu’s group when he is driven off by Kamen Rider Ghost, who reveals their world will be destroyed in 24 hours.