Hawaii Five-0: Season 8, Episode 21

8 - 21: Ahuwale Ka Nane Huna (The Answer to the Riddle is Seen)

Harry Langford enlists McGarrett and Danny's help to track down Lady Sophie, a teenage British royal who has run away while under his protection. Also, Grover, Tani and Junior work a 25-year-old murder case after a mysterious Betamax tape arrives at 5-0 headquarters.