It’s possible to conceal quite a bit when everything is dark. There have been numerous films centered around sightseeing vessels encountering trouble and their passengers becoming prey to nearby animals. Sharks, piranhas, alligators—even bizarre fish creatures—have appeared in these stories. This one features a hippo, which is an interesting twist. It’s rather charming, actually. I found the basic idea appealing, and the characters were developed well enough that I felt some genuine suspense, which was nice. The actors are adequate; they don't stand out particularly, but there's nothing wrong with their performances. And the filmmaking itself is completely acceptable. However, the hippo isn’t quite as impressive as one might hope, and the filmmakers seem to try to compensate for that by keeping it shrouded in shadow. Some viewers may find this creates a certain mood, but to me, it just made the special effects look inexpensive. It's remarkable how much better films like Jurassic Park appeared years ago, considering how rapidly technology has advanced. I suppose the creative skill simply isn’t present here. Naturally, this movie didn’t have nearly as large of a budget as Jurassic Park, but there was only one hippo to create. So it shouldn't have been too difficult to make it seem frightening. Despite its flaws, I did enjoy the film and will suggest it to anyone who appreciates movies about tour boats getting into trouble and tourists being devoured.

Source on TMDB