Returns to England from abroad where he has spent years with his father in the family business. On his father's death he falls out with his mother and gives up his share of the family business. He befriends Amy Dorrit at the Marshalsea and becomes business partner to Daniel Doyce. After losing everything in a banking scam by Merdle he is himself imprisoned in the Marshalsea. His health fails and Amy cares for him in the prison. The novel ends with Arthur and Amy's marriage.