The doctor’s human experiments are clearly fighting against their will! As Yusuke prepares to put them out of their misery, the Masked Fighter intervenes and suggests a peculiar plan.

Kuwabara's fight with the elder Toguro brother comes to a smashing conclusion, leading into Yusuke's grudge match with the younger Toguro. But before that bout can begin, intrigue at Team Toguro culminates in a shocking proposal from Sakyo and an even more shocking response from Koenma!

Despite his stunning victory at the Dark Tournament, Yusuke Urameshi learns firsthand that there are others wishing to challenge him. Yusuke makes the first mistake by underestimating the strengths of these new adversaries. With his best friend kidnapped, Kuwabara must round up the old gang in order to stage a rescue attempt...or suffer the consequences!

As Sensui's plan continues, Kuwabara and his friends attend a rock concert. However, they are ambushed by Sensui's next minion: Seaman, a person with the ability to create monsters out of water. With his friends held hostage, Kuwabara must battle Seaman alone...

Only two hours remain before the tunnel opens unleashing a horde of hungry demons upon the world of the living. Kurama steps forth to battle Gamemaster for the right to move on to Sensui's lair and Yusuke senses that one of them will not make it out alive.

Too late to save their friend's life, Kuwabara, Kurama, and Hiei unleash their most devastating attacks on Sensui, who retreats within the tunnel. King Yama reveals a dark secret to Botan. What news would cause her to tremble in terror? What does King Yama know about Yusuke that the others do not?

As the three strangers in Kuroko's house explain the reason for their presence, Yusuke begins to sense that something is amiss. These demons have come to him to reveal one thing: that Yusuke's ancestor resides as a king of Demon World! And unless Yusuke travels to Demon World soon, the balance of power could shift and spell the end of humans reign at the top of the food chain.

It's been nearly a year since Yusuke, Hiei and Kurama arrived in Demon World, each firmly enmeshed in its tense power struggle. Now, the three former teammates are in high positions on conflicting sides, as they head towards an inevitable clash. With Raizen's time drawing to an end, Yusuke must act fast in order to keep the tenuous peace in Demon World.