That's the whole problem with this film. The opening scene is fantastically done with Terry Lumley as Martha Sayers on the run from some unseen but clearly deadly menace that it seems can get to her no matter where she runs and/or hides. It's too bad this level of suspense and thrills could not be maintained when it was star Pamela Franklin's turn (as Elizabeth Sayers) to be terrorized at the school for girls her sister had previously attended. Sure a nice effort is made by a very talented cast including Roy Thinnes, Kate Jackson, Jamie-Smith Jackson and Lloyd Bochner to keep the excitement going but in the end this falters and loses that hard edge it had when it opened. Perhaps some of this is the fault of the limitations inherent in this appearing on television in the 1970s but honestly I feel the real reason is that they reveal too much in terms of clues and visuals making the previously terrifying and mysterious menace seem much less threatening when it is finally revealed, in fact it proves somewhat anticlimactic.