“Slumber” (*1/2 out of four) was a lumbering horror thriller virtually guaranteed to put viewers into a slumber about a sleep doctor (Maggie Q) who tries to protect a family from a vindictive demon that preys on people through their nightmares. Since originality is a challenge for horror movies nowadays, this manages to rip-off “Nightmare On Elm Street” but also “Poltergeist” and “The Shining” as well. Q’s sincere performance is wasted.