Faust calls upon nature to cure him of his world-weariness ("Nature immense, impénétrable et fière"). Méphistophélès appears and tells him that Marguerite is in prison. While awaiting Faust's return, she has given her mother the sleeping potion Faust had previously provided to calm her mother during their nights of love, and used it so often that she has killed the old woman, and now is to be hanged the next day. Faust panics, but Méphistophélès claims he can save her—if Faust relinquishes his soul to him. Unable to think of anything but saving Marguerite, Faust agrees. The two ride off on a pair of black horses.