While McGarrett sits in prison awaiting trial for the murder of the governor, Danny brings him a surprise visitor to help clear him. Meanwhile, Kono is suspended from the force, pending an internal investigation.

Gov. Denning assigns Officer Lori Weston to Five-0 to make sure McGarrett and team follow the new rules set by him and also apply her excellent profiling skills to the task force. Meanwhile, as Five-0 investigates the kidnapping of a teenage paddleboard champion, Internal Affairs Capt. Vince Fryer continues his interrogation of Kono.

At his mentor's request, McGarrett persuades Max to redo the autopsy on a SEAL, thought to have committed suicide, in order to investigate his murder. Meanwhile, Chin Ho worries about Kono hanging out with a group of dirty ex-cops, including Frank Delano.

The FIVE-0’s investigation into the murder of the state’s women’s volleyball coach leads them to find out more bad news about Kono, and Chin Ho reconnects with his former fiancée, Malia.

McGarrett and the Five-0 search for a busload of kidnapped school children as well as the people responsible.

On the eve of Chin Ho’s wedding to Malia, the Five-0’s investigation into a man left for dead in an abandoned WWII bunker crosses paths with Capt. Fryer’s case of a Jane Doe.

When the Five-0 team discover that the murder of a High School girl was a professional hit, they must find out why she was targeted before they can find her killer.

Chin Ho shares news about Joe White that rocks McGarrett to his core; Danny is forced to play midwife when his ex goes into early labor.

When Danno and his family are targeted by a vengeful dirty cop from Danno's past, the team steps in to help.

When the team almost causes an international incident, Lt. Gov. Denning decides that one of them should be fired; Chin Ho faces the harrowing task of choosing a Valentine's Day gift for Malia.

A murder case hits close to home for Max when he is convinced that The Trashman, a serial killer with ties to his past, is on the loose. In order to convince Five-0 of his suspicions, Max reveals shocking information about his childhood.