The Cure for Madness

 is a quest in The Elder Scrolls V: Skyrim.

Overview

 * Prerequisite: Breaching Security
 * Quest Giver: Astrid
 * Reward: Shadowmere
 * Reputation Gain: N/A
 * Known Bugs

Background
"When I was away, Cicero went berserk and tried to kill Astrid. He fled to the Sanctuary, with Arnbjorn in pursuit. I need you to locate them, and then kill Cicero."

Walkthrough
After you arrive in the Sanctuary, talk to Astrid. She will inform you that Cicero went crazy and attempted to kill everyone before fleeing. She instructs you to search Cicero’s room for clues. On a table in his room is Cicero's journal. When you read it, will provide you with details of the password and location for an older and unused Dark Brotherhood Sanctuary near Dawnstar. You must let Astrid know of this, and upon doing so, she will send you after Cicero and provide you with her horse.

Obtain the horse, Shadowmere, and travel to Dawnstar (you may fast travel). Talk to Arnbjorn outside of the Dawnstar Sanctuary. Tell him to go back home and that you will go after Cicero. Enter Dawnstar Sanctuary, follow the linear path (fighting the guardians, and a troll, whilst avoiding traps) to Cicero. When you find him you must decide to either kill him or spare him. Whatever your choice may be, report back (if you spare him, you will lie) to Astrid about Cicero’s fate.


 * If you have the Ghost of Lucien Lachance active, Lucien will tell you that it is not wise to kill Cicero, because Keeper is a sacred position in the Dark Brotherhood. Having completed the questline for the Dark Brotherhood, and Cicero is still alive, he becomes a Follower.
 * If you try to pickpocket Cicero and he catches you, he will stand up and attack you, forcing you to kill him. However, you can get 500 from pickpocketing him and then another 500 spawns after killing him. (This bug is fixed)
 * If you kill Cicero, loot his armor set, raise him (Conjuration) and than bring him through a new loading screen his armor will respawn on his body. -Note- It seems that if you raise Cicero before you report back to Astrid, the game won't allow you to talk to her and you will never be able to finish the quest (Even if you kill your Cicero zombie).
 * Although you can't loot the guardians after you kill them, you can pickpocket them for Shrouded Armor pieces and weapons/arrows, if you have the Misdirection and Perfect Touch perks.