Director: David F. Sandberg. Cast: Teresa Palmer, Gabriel Bateman, Maria Bello, Alexander DiPersia. 81 min. Rated PG-13. Horror.
I'm neither giving this a NoMo because almost the entire story is ruined in the trailer, nor because it copies winning script elements from the 2002 horror, The Ring (young heroine, younger boy, evil female entity from psychiatric ward, victimized innocent boyfriend, ...). It fails, because the viewer is dragged to an ending (unspoiled by the trailer!) that makes no narrative sense, not even within its fantasy/horror logic. An entity can either materially/spiritually exist in the outside world and terrorize characters, or be an abstraction of one character's mind and torture that one person. You can't have both.
PS: Batman v Superman, The Conjuring 2, X-Men: Apocalypse, Independence Day: Resurgence, Cell, Ghostbusters, The Purge 3, Star Trek Beyond. I don't remember ever branding so many summer movies with back-to-back NoMos and SoSos. And now Lights Out earns 77% on the Tomatometer! It's a bad sign when The Shallows is your summer's most entertaining movie.