Khartoum is a supremely powerful, evil sorcerer imprisoned on the cover of a large magical book by his longtime enemies. His only hope of release is a magical gem called the Philosopher's Stone which contains the god-like energy and abilities of the cosmos itself. All he needs is someone greedy enough to create the stone and willingly release him from his prison. As it turns out, Mozenrath is that "someone" when he finds the book. After the young wizard creates the stone, Khartoum double crosses him and takes the stone for himself. Khartoum likes a power-hungry wizard.
In the episode, Mozenrath tries to find a new way to gain more power so as to conquer the world. In his Citadel, he brings a book known as the Book of Khartoum, which contains the key to all of the magical secrets in the cosmos and which took him 7 years to search in the 7 Deserts. Khartoum is seen as a normal book with an angry wizard face but after Mozenrath, who is worthy of Khartoum's magic, releases him, he comes to life, his eyes turn red permanently, and floats. When Khartoum finds out that Mozenrath is a power-hungry wizard, which of course, he likes, he tells him that the key to all of the magical secrets in the cosmos is held within a magical gem called the Philosopher's Stone. Khartoums tells him that he needs to build a furnace to heat a small quantity of sands, crystals, flakes of gold and one element that is absolutely essential; a cosmic power source strong enough to heat the furnace (namely, Genie) so as to create the magical gem.
After Mozenrath builds the furnace and kidnaps Genie, Genie isn't powerful enough to heat the furnace. So now, Mozenrath must get more power, or his dreams of unlocking the cosmos's greatest secrets will be dashed forever (namely, Eden). After tricking Eden into letting her exchange her place with Genie, Eden and Genie both end up in the furnace, thus, making them powerful enough to heat it while aging fast.
After the Philosopher's Stone is created, Mozenrath opens the furnace and removes the Philosopher's Stone, but it then floats out of his hand towards Khartoum. The Stone embeds itself in Khartoum's "turban" and then, Khartoum's body rises out of the book, therefore, he has been released from his imprisonment. It is revealed that Khartoum double crossed Mozenrath and used him, he just needed someone greedy enough to create the stone and release him from his prison. After zapping Mozenrath, Mozenrath tries to return the favor but it is proven that his powers are useless against him while Khartoum's are limitless.
Later, Khartoum begins to grow rapidly until he reaches the ceiling, which means that the Philosopher's Stone is getting much stronger and so is he. Then, he and Mozenrath have a magic fight, nevertheless, Mozenrath's magic is still proven useless against Khartoum and then, his powers disappear all of a sudden. Khartoum grows so large that now, his head is sticking through the roof of the Citadel.
While Khartoum is distracted by Genie; who he and Eden have their powers and ages restored due to the Genie Embrace, Eden unwinds Khartoum's turban, causing the Philosopher's Stone to fall out. Genie puts on oven mitts and catches the mystical Philosopher's Stone. Khartoum starts to shrink and is pulled back inside his magical book again. Finally, the Stone is forever destroyed by the two genies' combined magics and Khatoum suddenly disappears too.
Khartoum (before he is brought to life by Mozenrath)
Khartoum in book form (during his imprisonment)
Khartoum in his human form (after his release)
"It's been many centuries since my enemies trapped me inside this accursed book. But now, with the Philosopher's Stone in place, no one shall ever imprison me again."