The Bargain is a quest in Fable II that forms part of The Hero of Will. After witnessing Garth's capture at the conclusion of the Hero of Will quest, Theresa will ask you to return to the Chamber of Fate. There, she'll explain that Lucien cannot be allowed to keep Garth captive. You must get him out of the Spire, but you don't know the first thing about how to go about doing just that. Theresa suspects that Lucien's former butler, Jeeves, might be able to provide some insight into the situation.