XTRO: Watch the Skies Synopsis & Summary

In this terrifying science fiction drama, a Marine platoon is assigned to a desert island, where as part of their mission they're told of a terrible secret. The government has not only been aware of visits by creatures from other worlds for years, they have several aliens in captivity and have been performing brutal medical experiments on them. One of the aliens escapes, however, and is now determined to get revenge on his tormentors. - Mark Deming, All Movie Guide