A couple's murder leads the team to investigate their two sons while McGarrett is shocked when Aunt Deb returns to the island with her new fiancé.
After a couple is murdered the team suspects that their two sons may be responsible.
Aunt Deb comes into twon to visit Steve. She introduces Steve to Leanard and informs him that her new boyfriend is her fiance. Steve becomes suspicious of Leanard when he sees him with a lot of cash and acting like a lawyer.
Steve and the team chase down Tye Gabel as one their first suspects in the case.
Steve looks into Leanard's background and discovers some unsettling news. He approaches his aunt about Leanard's past with the mob and she admits that she already knew.
The team follows one of the sons to a motel where they discover that he has been having a relationship with his best friend's mother, Patty. The team looks into the lawyer as a suspect and follows a trail of money that leads to a hired hitman.
After shooting the hitman, the team discovers evience on his computer that points to the mother Kate as the killer.
Steve attends the wedding of Leanard and his aunt.