Steve McGarrett returns home to Oahu, in order to find his father's killer. The governor offers him the chance to run his own task force (Five-0). Steve's team is joined by Chin Ho Kelly, Danny "Danno" Williams, and Kono Kalakaua.

An attempt to weaponize a machine capable of opening portals to other worlds fails, and instead creates an exponentially expanding "bubble" of fractured space-time. A team of specialists must enter the disturbance and make their way down a rabbit hole of increasingly more dangerous alternate realities in the hopes of finding and shutting down the machine which created it. However, someone-or SOMETHING-seems determined to stop them before the "bubble" engulfs the entire universe itself.