Picking up where Season 3 left off, we find McGarrett and Wo Fat cornered by unknown assailants in a detainment facility in season 4 of Hawaii Five-0, forcing McGarrett to break the law and turn on his own in order to find a kidnapped Catherine. Meanwhile Kono and Adam's secret location in Hong Kong is compromised, and Kono and Adam fight to stay alive when their hidden location is discovered.