Lewis Sezon 4 Odcinek 3: Sudden Death Question

On Halloween a university friend of pathologist Laura Hobson is found dead with a stake through her heart, and Lewis and Hathaway are approached by a physic medium who claims that they are in grave danger. The next day a student is murdered in the house that Hobson shared with her friends at university, and a clue 'from beyond the grave' at the crime scene leads Lewis and Hathaway to a third victim... As the body count rises Lewis and Hathaway are forced to acknowledge that Laura Hobson might know more about these deaths than she is letting on...