Nothing But the Night (1975)

When various trustees of the Van Traylen Orphanage begin dying in close order its at first written off as a coincidence But when a school bus accident very nearly takes out three more of them along with a group of orphans Col Bingham Christopher Lee and his pathologist friend Mark Peter Cushing begin looking into the deaths They come to think the answer lies with one of the girls on the bus who has vivid memories of things she could not possibly have seen