Hawaii Five-0: Season 4, Episode 1

4 - 1: Aloha Ke Kahi I Ke Kahi (We Need Each Another)

After McGarrett and Wo Fat narrowly escape from maximum security, gunmen storm Five-0 headquarters, compromising Kono and Adam's secret location in Hong Kong and forcing McGarrett to break the law and turn on his own in order to find a kidnapped Catherine, on the fourth season premiere of HAWAII FIVE-0.