University College Hospital

A spectral nurse, thought be some to be Lizzie Church, who accidentally killed a patient with a wrong dose of morhine and then killed herself, is said to walk the wards, wearing Edwardian uniform. It is said that some patients have praised the nurse in old-fashioned clothing for her kindness - but no one else on the ward saw her. An extension of the story says that she guides the hand of staff who inject morphine, to prevent a repetition of her mistake.

Link: The Londonist

Link: MyLondon