This episode tells the story of what happened days before McGarrett joined the 'task force' also know as '5-0'.
Rick Yune, who plays Han Ji-Woon (the North Korean terrorist leader), played the villain "Zao" in the James Bond movie Die Another Day (2002). Zao was the main henchman to that film's primary villain, "Colonel Moon," played by Will Yune Lee, who plays Five-0 adversary (and occasional ally) Sang Min.
Title translates to 'the promise' per Netflix
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