Hawaii Five-0 opens it’s Fourth Season with Kono (Grace Park) and Adam (Ian Anthony Dale) on the run in the middle of the Pacific Ocean and McGarrett (Alex O’Loughlin) and Wo Fat (Mark Dacascos) surviving the team of soldiers sent to kill the prisoner. While interrogating the lone surviving assassin, who Chin Ho (Daniel Dae Kim) identifies as the nephew of the NLM leader (Nestor Serrano), Five-0′s headquarters is laid siege to by a NLM terrorist cell (led by Martha Higareda and Henry Ian Cusick) who arrive not to save their comrade but to kill him before he talks.
By taking hostages and rigging the building’s exits with explosives the terrorists keep the police outside from storming the building and force McGarrett and Danny to return the NLM soldier to his comrades before they kill the man and promptly surrender to Five-0. Although his team makes it out without injury things don’t get any easier for McGarret, as the NLM leader kidnaps Catherine (Michelle Borth) and demands the return of his people in exchange for McGarrett’s girlfriend.
Although Five-0 manages to track down and kill all the terrorists before they make it off the island, McGarrett’s antics make a potential enemy out of Captain Grover (Chi McBride) and that’s not the only bad news. With the help of Danny’s hacker buddy (Martin Starr), Five-0 discovers what information the NLM downloaded from Five-0′s servers and that not every member of Five-0 is safe after all.
Although the final 10-minutes of the episode enable McGarrett to play Superman (to such the extent even Danny comments on it) neither the super genius plan of the NLM (for everything except their escape) nor McGarrett rash (even for him) decision of hijacking the SWAT van work as well as they should. That said, the premiere certainly ratchets up the tension, and ends on cliffhanger with yet another member of the team in serious jeopardy thousands of miles away.