After Tsukasa suddenly loses his powers, he learns from Kaito that he is actually in the World of Negatives. He later is seen by a talent agent and is offered to be signed onto his agency to become an idol. Although Yusuke acts as the voice of reason, he gets caught up in the fame seeking as well. Meanwhile, after her school friends return while waiting for Chinatsu, Natsumi that suggests that they should dig up the "treasure" they buried together, only to find that a parking lot was built over it and learning that Chinatsu moved their treasure prior. Once, Tsukasa finds Natsumi, he attempts to tell her that they are not in the real world, but Natsumi refuses to accept this as she runs off to the TG Club's hideout where she also meets the World of Negatives's Natsumi. Confirming that Tsukasa is right and revealing that the world is a heaven for monsters with only a few survivors left in hiding. Furthermore, the Dark Riders had murdered the real TG Club members' Negative counterparts and assumed the males' identities with the other Natsumi the only survivor. It is then that the Dark Riders arrive to further prove the other Natsumi's words as they force her to dig up the Dark Riders' treasure she buried: the K-Touch. Otoya is prepared to give it to Tsukasa so he can become the Ultimate Rider until Diend intervenes by attacking the Dark Riders. Though Otoya offers him the world on a silver platter, Tsukasa refuses and he regains his powers. Using the K-Touch, Tsukasa transforms into Decade Complete Form, destroying Ryuga, Orga and Dark Kabuto with the powers of Ryuki Survive, Faiz Blaster Form, and Kabuto Hyper Form, respectively, as Otoya escapes destruction. After the other Natsumi bids farewell to her counterpart and Tsukasa, to whom she gives the K-Touch, the group returns to the Hikari Studio to resume their journey home with their next stop being Daiki Kaito's home world.[21]
