The team investigates a downed, top-secret Chinese satellite. Retrieving the satellite's schematics, Jerry is cornered by a Chinese spy, Zi, but Jerry manages to capture her. Zi appeals to McGarrett to let her help track the rogue operatives, who are looking to profit from data on the satellite's hard drive. Zi's information helps Jerry pinpoint the location of the rogue operatives. Catherine reveals Zi was engaged to the mastermind behind the operation, but, during the takedown, Zi proves herself by killing her fiancée and retrieving the hard drive. Jerry, spooked from his encounter with Zi and fearing retribution, goes to stay with McGarrett. Meanwhile, Grover takes Clara, Danny's mom, on a ride along.