The Ruins is, with one major caveat, about as good an adaptation of Scott Smith's best-selling novel as Hollywood was ever going to make. Smith's book - about a group of college kids who stumble onto a hill in the Mexican jungle where a flesh-eating vine dwells - was the kind of relentless beach read that seemed tailor-made for the movies, at least until you realized you were dealing with a story about a talking plant that drinks blood.
That would be fine if you were making Little Shop of Horrors. But if you're aiming for the grueling horror picture that director Carter Smith is after, then the challenge becomes practically insurmountable. No matter how good your special effects crew, no matter how strong your cast, your movie is going to live or die on the whim of some shrubbery.