A Name Written In Water - S2.E8

With Robert in a coma at the hospital, Alison rushes to his bedside, finding Jude there, who is less than happy to see her. Whilst in the hospital, waiting, the psychic witnesses a strange nurse wandering the corridors. This is confirmed by many of the workers, who have heard rumours about this unusual being. Why is she there - and does she mean the end for Robert?