Five-0 is assigned by the CIA to find a missing federal prisoner after the plane he is being transported to Oahu on arrives without him, but instead has four dead bodies. After being set up for a murder, Kono finds herself on the outs again with the police force. Steve has another surprising encounter with Wo Fat. Danny reconnects with Gabrielle.moreless
Doris needs Steve's help on a clandestine mission to take back an incriminating microfiche. Kono is in jeopardy whilst getting closer to finding out Adam's secret.
A member of a local roller derby team falls to her death in front of Dog the Bounty Hunter, as he is arresting a fugitive just a few feet away. Catherine is sent in undercover as a new member of the derby team. Steve finds out that Catherine kept a secret from him involving his mother and questions whether he can trust her.moreless
The daughter of a murdered Lua master comes to Hawaii Five-0 for help. Steve decides to have a private investigator keep tabs on his mother.
When a therapist's patient is murdered, Steve finds evidence that the therapist may be involved. Catherine finds herself mixed up in Doris' past, when a former target is looking for payback.
Steve attempts to arrange a reunion between his mother and sister. When a young computer hacker is murdered Hawaii Five-0 steps in.
Steve's attention is divided between their current investigation into a Polo players murder and the return of his mother.
The team goes after Wo Fat and Delano for the death of an important person. Steve must resolve the issues between him and his "dead" mother, once he finds her alive and well.moreless