故事紧接上一季结尾：夏威夷州长遭谋杀后，Steve McGarrett成了头号嫌疑人，被临时羁押在监狱里等候出庭受审。Danny突然带着能够洗清他罪名的证据前来探监。与此同时，Kono遭到停职检查的处分，内务调查部派人对她展开全面调查。Terry O'Quinn在本集中扮演McGarrett在海豹突击队受训时的指挥官Joe White；Richard T. Jones扮演新任夏威夷州长Sam Denning；William Sadler再次扮演McGarrett的父亲John McGarrett。

A group of aliens has come to Earth to learn about its population, customs, etc. To avoid detection, they have taken on human form which gives them human emotions, physical needs etc. WITHOUT the understanding of what they mean or the inhibitions normally present in humans. Their leader takes the position of a college professor, their military expert as his sister, their intelligence expert, supposedly oldest of group takes form of his teenage son. The uninhibited reactions turn everyday events into unusual situations.