With rising international tensions in the Indo-Pacific, a brilliant and eclectic team of U.S. NCIS agents and the Australian Federal Police (AFP) are grafted into a multinational taskforce to keep naval crimes in check in the most contested patch of ocean on the planet.

Led by NCIS Special Agent Michelle Mackey and Sgt. Jim "JD" Dempsey, the team of Americans and Aussies must quickly learn to trust each other, overcoming and harnessing their differences to solve each case.

Though jurisdictional tussles and culture clashes make for a rocky start, Mackey comes to respect JD's nose for the truth, and JD comes to respect her maverick style. Meanwhile, sassy AFP Constable Evie Cooper and endlessly curious Special Agent DeShawn Jackson form a fast friendship, while curmudgeonly forensic pathologist Dr. Roy Penrose meets his match in the brilliant young forensic scientist Bluebird "Blue" Gleeson.