Blake Lively, whose best role until now was the secretary in that SNL “Potato Chip” sketch, is terrific as Nancy, a medical school dropout who goes to a secret beach in Mexico in the wake of her mother’s death. She sets out for a day of surfing and reflection in what she thinks is a completely solitary setting (with the exception of a couple other friendly surfers). Turns out, there’s a big-assed Great White shark, and this would be it’s part of Earth, and no trespassers are allowed, even if they are as pretty as Blake Lively.

As shark movies go, this is a good one, with decent CGI effects, a couple of tense shark attacks, and a constant level of terror that never lets up. The only thing really keeping this from being “very good” rather than “nice and good” would be the ending, which made me laugh a laugh I shouldn’t have laughed. Even with the big flaw, this is one of the summer movie season’s more fun offerings, certainly a lot more fun than that one with aliens and Jeff Goldblum in it.

Note to producers: Please don’t make a sequel where the shark’s offspring follows Blake Lively to a vacation resort, Jaws: The Revenge style. You’ve made an all time top ten shark movie; quit while you are ahead.