Ho’onani Makuakane (Honor Thy Father) – A murder attempt on a Pearl Harbor veteran leads Five-0 to use decades old evidence to investigate a deadly crime committed in an internment camp on Oahu during WWII.
Hau’oli La Ho’omaika’i (Happy Thanksgiving) –
Five-0 investigates the murder of a secret service agent just as the president travels to Oahu. Meanwhile, McGarrett’s aunt visits and brings with her a shocking secret.
Akanahe (Reluctant Partners) – McGarrett and Grover are forced to work together to protect national security when the governor orders them to serve a warrant to a young computer hacker.
Ua Nalohia (In Deep) – McGarrett investigates the murder of an undercover ATF agent and cares for Mary’s newly adopted baby when she gets sick.
Kupouli ‘la (Broken) – When Halloween comes to Hawaii and a zombie-like man is shot, Five-0 races to stop a madman who is conducting experiments on humans.
Kupu’eu (Fallen Hero) – Catherine’s seemingly harmless surveillance job turns deadly. Meanwhile, Adam considers making the ultimate sacrifice to save Kono.
A Ia La Aku (From This Day Forward) – A wedding crasher is murdered and the prime suspect is the runaway bride. Meanwhile, Danny makes a big decision in his relationship with Gabby.
Ka ‘oia’i’o Ma Loko (The Truth Within) – A conspiracy theorist helps Five-0 investigate a double murder. The probe reveals that a missing artifact may be the key to solving the homicides.
A’ale Ma’a Wau (Fish Out of Water) – A Texas Ranger comes to the island to find his missing daughter, and the Five-0 team gets involved when murder happens. Meanwhile, Kono and Adam’s hidden location.
Aloha ke kahi I ke kahi – McGarrett and Wo Fat narrowly escape from maximum security as Season 4 begins. Meanwhile, gunmen storm Five-0 headquarters and kidnap Catherine. To rescue her, Steve is forced to break the law and go up against a tough new SWAT commander. Also: Kono and Adam’s secret location in Hong Kong is compromised.