Plot hole: When Diana turns up at her director friend's house she finds it crawling with cops as his girlfriend Christie has been murdered and the house is now a crime scene. She explains she lent Christie a coat and is there to pick it up - and a cop helpfully finds it on the floor and hands it to her. Are we to believe that a homicide policeman will hand over an artifact from a murder scene to an unidentified woman without making any attempt to confirm her identity, or even if the coat is even hers!? They don't even ask.