Five seemingly good citizens with different motives band together to steal $6,000,000 while McGarrett is away on Maui at a trial.

McGarrett must deal with the conflicts between four gangs of differing ethnic background, and try to uncover illegal activities.

A doctor tracking venereal disease is murdered, and Five-O must track the series of encounters to find out who is a carrier. Their investigation is made doubly important by the murder of a young woman who is close to a upcoming politician. He seems a likely suspect but McGarrett suspects a deeper plot.

When McGarrett arrests a group of vigilante nationalists, hidden bombs at the courthouse threaten to destabilise the islands.