The Intruder, Part 1.Thief King Bakura, arrives at the palace to claim the Millennium Items for himself. The priests engage him in battle, but Bakura the Thief King's spirit beast, Diabound, proves too much for them to handle, until the Pharaoh steps in and summons Obelisk the Tormentor. However, Obelisk happens to be evenly matched with Bakura's Diabound, which is enhanced with power that it stole from Kaiba's Blue-Eyes White Dragon, during Yami Bakura's previous Duel with Seto Kaiba. Meanwhile, the spirits of Yugi and the others enter the Millennium Puzzle, thanks to the help of Shadi and his Millennium Key, in search of a doorway into the Pharaoh's memories, which would take them to the memory world that the Pharaoh had entered.