Dr. Akujirou is the very person who was researching the mysterious bitter melon, and his mind is currently in a dog after accidentally tapping into its body-swapping power! Now the doctor has gone missing, and Shinichi and Ichigo have set out to find him--only to have an assassin from Akujirou's organization get in the way. The two are completely outmatched, and with Shinichi on the brink of suffocation, Ichigo only has one option left...