Sheogorath has an old deal with Arch-Mage Shalidor in which the Vestige has to help Shalidor re-obtain all of his lorebooks that are not readable by Shalidor's own eyes due to a special enchantment that Sheogorath placed on the books out of entertainment.
This forces Shalidor to ask his assistant to translate the books for him at a slower pace. However, the books, little to Shalidor's knowledge were enchanted to drive his assistant "mad" resulting in a decision made by the Vestige at the end of the questline. The choice is a dozen Skyshards as a reward or a removal of the madness effect on the assistant, freeing her from her curse. If the choice is taking the Skyshards, Sheogorath will take the assistant with him back to the Shivering Isles.
A high-ranking member of the Mages Guild, Valaste wants the Vestige to perform a task for her. They must find a ruin nearby, which Valaste says may hold a store of ancient knowledge.
Valaste can't find anything in "Circus of Cheerful Slaughter" that tells her what the next of Sheogorath's trials is. She lets the Vestige try to read the book, and they are transported to Circus of Cheerful Slaughter.
In the final test, Sheogorath wants the Vestige to take a vacation in his family's chateau. However, all the three guest rooms are occupied, and two guests are cannibals. The correct guest is the one that isn't playing his role right and wants to get out. Next, the Vestige must find their way through a dark maze. Finally, they must fight their way through Madmen and Madwomen to a boss fight with Uncle Leo, a flesh atronach.
The Vestige and Shalidor journey to Eyevea, but Sheogorath left portals to Oblivion open and the island is covered in daedra. The Vestige fights Haskill. Sheogorath, who has been making Valaste slowly insane with his cursed books, offers to take her to the Shivering Isles. They can decide whether or not to save her.
|Show: The Mad God's Bargain|
"You made it this far, just as I had predicted. I am glad to see that my calculations were not in error. Now, if you are ready, we have a prison to break out of."
How did you wind up here? "I was captured shortly after Meridia pushed her city into this dread realm. This prison relies on darkness. Early on, I almost broke free. Now Molag Bal shapes the darkness itself to bind me, suppressing my attempts to escape."
"Let us not dawdle in this vile place. Find me in the Hollow City and speak to me there."
"I have barely set foot within these hallowed walls and I already feel a thousand times better! And now that you are here, we can determine our next move against the vile Molag Bal."
Do you have a plan? "I must take stock of our assets and resources. Determine just how much might we can bring to bear. Only then can I develop a strategy that shall allow us to win this war. But forgive me. I wanted to convey that you performed admirably at the tower."
|Show: The Grip of Madness|
"Well, if it isn't my old friend Hunts-For-Books! Now don't look so glum, or the skeevers'll notice. Then they hit you up for some spare gold, a few shin bones, your best pair of cheese-filled slippers. Insufferable beasts! They can't hold a conversation."
What do you want?