chunk: Mephisto can get him to be satisfied and to want a moment to last forever). Faust signs in blood, and Mephisto first takes him to Auerbach's tavern in Leipzig, where the devil plays tricks on some drunken revellers. Having then been transformed into a young man by a witch, Faust encounters Margaret (Gretchen) and she excites his desires. Through a scheme involving jewellery and Gretchen's neighbour Marthe, Mephisto brings about Faust's and Gretchen's liaison. After a period of separation, Faust seduces Gretchen, who accidentally kills her mother with a sleeping potion Faust had given her. Gretchen is pregnant, and her torment is further increased when Faust and Mephisto kill her enraged brother in a sword fight. Mephisto seeks to distract Faust by taking him to the witches' sabbath of Walpurgis Night, but Faust insists on rescuing Gretchen from the death sentence she has been given after going insane and drowning her newborn child. In the dungeon, Faust in vain tries to persuade