Lady Mary is a character in Episode 3 of Series 5. She is portrayed by Amanda Hale. She was killed by Hal over two centuries ago, but remained behind, believing that her presence kept him from killing. She suffered a temporary breakdown when she learned that Hal had succumbed to his bloodlust over the last two centuries, even attempting to stake him, but Alex convinced Mary to let him go, informing her that she and Tom would take responsibility for Hal's continued abstention from blood.