Kopi wale no i ka i’a a ‘eu no ka ilo. (Though the Fish is Well Salted, the Maggots Crawl.) – Five-0 must help Duke after he is forced to steal crucial evidence from the police locker in exchange for his kidnapped granddaughter. Also, Jerry goes undercover at a mental health facility in order to solve a murder.
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.
He lokomaika’i ka manu o Kaiona (Kind is the Bird of Kaiona) – Catherine Rollins recruits McGarrett and Jerry to help her track down a uranium deposit thought to be hidden on an abandoned Hawaiian island before a suspected terrorist can make dirty bombs with it. Also, when Junior falls and is trapped in a ravine, he reflects on his estranged relationship with his father.
Aohe mea make i ka hewa; make no i ka mihi ole (No one has ever died for the mistakes he has made only because he didn’t repent) – A hitman McGarrett’s father failed to arrest comes to McGarrett to finally confess his crimes and admit where he buried his victims. Also, Jessie makes a dangerous decision that could ruin Adam’s life.
E ho’oko kuleana (To Do One’s Duty) – The ex-wife of the man who shot Danny comes to Oahu and reveals how Danny’s protection during a dangerous domestic dispute when he was in New Jersey helped save her life. Also, Tani and Junior are assigned to walk the beat as uniformed officers for the day, and Adam is framed for the murder of the crime boss he has been tracking
Holapu ke ahi, koe iho ka lehu (The Fire Blazed Up, Then Only Ashes Were Left) -Adam’s mission to take down organized crime on the Island goes sideways when deadly chlorine gas he was using to bait a big fish falls into the wrong hands. Also, Adam begins to doubt Jessie’s allegiance.
O na hoku o ka lani ka i ‘ike ia Pae’ (Only the Stars of Heaven Know Where Pae Is) – Tani and Junior go undercover as prospective parents in order to infiltrate a private school where the headmaster was murdered. Also, Adam’s life is on the line when he is held captive and forced to produce a hidden massive amount of money.
He puko?a kani ?aina (A Coral Reef Strengthens Out Into Land) – McGarrett and Danny investigate the murder of a private detective whose client was killed the same way, and Adam sends Jessie into a dangerous situation with disastrous consequences. Also, Danny’s uncle, Vito, comes to town to help Danny and McGarrett get their restaurant up and running.
Na keiki a Kalaihaohia (The Children of Kalaihaohia) – When the corpse of a diamond smuggler is stolen from a graveyard, Five-0 tracks down his partner, Voss, who will stop at nothing to retrieve their latest batch of contraband. Also, Adam recruits a new confidential informant, Jessie Nomura; Tani gets a devastating call; and McGarrett tasks Pua to find his and Danny’s stolen tools.
O ka mea ua hala, ua hala ia (What is Gone is Gone) – When a man accused of killing his wife threatens to commit suicide, Grover reveals how he too was once on the brink of taking his own life.