Please answer the following question: Given the following context:  Following top secret experiments, people called "viewers" have developed the psychic ability to enter people's memories. John Washington, a recent widower, is one such gifted individual or "viewer." Washington works for Mindscape, the world's top memory detective agency, which offers the abilities of their psychic employees to help solve criminal cases, although their findings aren't yet recognized as evidence in court. During a session that goes wrong, John suffers a stroke and is left incapacitated for two years. Financially ruined, he still owns the beach house where his wife died, but refuses to sell it. Desperate for money, John asks his old superior, Sebastian (Brian Cox), for a new job. The case he receives is that of a brilliant but troubled 16-year-old girl, Anna Greene, who is on a hunger strike. Her stepfather wants her sent to a mental institution, which Anna's mother and Anna herself are adamantly against. John is sent to end her hunger strike. John and Anna begin their therapy sessions, focusing on Anna's time at a prestigious girl's school and several incidents that happened there. John finds himself drawn to Anna, while, at the same time, remaining wary of her. Anna's maid, Judith, who John had just started dating, is thrown down the stairs, and Anna is blamed for the incident. John also harbors suspicions towards Anna's stepfather, who he believes has hired a mysterious man to shadow him, as well as towards Sebastian, who John learns has withheld a file on Anna from him. Anna's behavior towards John becomes more flirtatious, and she draws a portrait of him with the caption, "You are my only safe place."  answer the following question:  What is the last name of the person who has therapy sessions with John?
Answer:
Greene