"The Evil Masters" (知っていたバビディ Shitteita Babidi, lit. "Bobbidi Knows") is the two hundred fifty third chapter of Dragon Ball Z and the four hundred forty-seventh overall chapter of the Dragon Ball manga.
Kibito and Supreme Kai freak out that Babidi has taken control of Dabura, king of the Demon Realm. Goku asks if he's the big guy, and Supreme Kai says yes. He explains that he's the king of the Dark Demon Realm. In this world, they may be the strongest, but in the Demon World, Dabura is the top. Krillin starts to get worried, as Gohan realizes the smaller one must be the Mage Babidi. Supreme Kai says he has little strength, but he uses fierce magic, enough to make even Dabura his underling. It's not just that his magic is powerful enough to enslave really strong people, Babidi takes advantage of the evil in one's heart and controls them via their thoughts. Thus, Dabura was a suitable choice. That's why only people like them without evil in their hearts can fight Babidi.
Supreme Kai says they really hadn't counted on Dabura being here, and Vegeta asks if they think they can't win. Vegeta says this Majin Buu won't be revived, because he won’t lose to guys like this. Goku tells Krillin he should leave, and Krillin agrees. Meanwhile, Babidi says the energy device is full, and is fairly close to the amount they need to revive Majin Buu. But now he doesn't need those two anymore, and Babidi suddenly makes Spopovich swell up until he explodes. Yamu tries to run away, but Pui-Pui takes care of this by firing a blast at Yamu, killing him on the spot. Babidi says he's noticed they had brought along lots of "bait", including his father's killer, Supreme Kai. Dabura figures they intend to hide, noting that there's seven of them. They can't use Supreme Kai or Kibito's energy, but three of the others have wonderful energy.