(On Cable TV, January 2017) There is a welcome high-concept simplicity to The Shallows that sets it apart from so many other humdrum efforts. Here, a surfer is injured and stranded on a small island in an isolated bay, with an unusually tenacious shark circling her for food. It sounds like a thin premise even for a 90-minute movie, but the script does have enough in the tank to sustain the film to the end with a minimal amount of flashbacks outside the claustrophobic situation. Blake Lively stars in a film that features her (and only her) for most of its running time—a demanding physical role in which she’s battered, bled, driven to madness and showing a fairly wide range of emotion for a single-location film. Still, the most valued player here is director Jaume Collet-Serra, bringing his usual madness to a script that benefits from his kind of excessive showboating. On-screen text messages are familiar by now, but it’s when Lively is stuck on the rocks that Collet-Serra gets at his best, cleverly establishing a good sense of place before letting loose with a surprising variety of action sequences. The Shallows earns a special place as a minimalist premise maximally executed: It’s quite a bit of fun to watch, and there is seldom a dull moment. The shark makes for an implausible antagonist, but every great movie can use a great villain, so that’s the role it plays. Lively is quite good in a tough role (no wonder she’s emerging as one of the most capable actresses of her cohort—also see what she could manage in The Age of Adaline) and the film’s conclusion is suitably grandiose. The Shallows is a nice surprise find, especially for those who assumed this would be just another shark movie.