One the eve of the election the Governor Denning (Richard T. Jones) asks the Five-0 Task Force to discreetly investigate the murder of a a dead prostitute found in the mansion of good friends of the Governor. After talking with the victim’s roommate (Alicia Ziegler), Chin-Ho (Daniel Dae Kim) and Kono (Grace Park) find themselves tailed by a black SUV with the Governor’s plates and McGarrett (Alex O’Loughlin) discovers the lab is dragging their heels on DNA evidence at the request of the Governor’s office. Confronting the Governor, McGarrett discovers the frontrunner to be named Hawaii’s next Senator (Wiley M. Pickett), and another friend of the Governor, was staying in the house where the woman was killed. And now both the Congressman and his Chief of Staff (Stephanie Jacobsen) are missing.
The DNA on the victim’s body matches an English professor from Ohio (Patrick Fischler) on his way off the island who had sex with the victim hours before her death but alibis out of the murder. The Chief of Staff finally turns up and although she’s able to fill-in some of the blanks (such as admitting she’s the one who procured the prostitute and delivered her to the Congressman) she has no idea where her boss is or what happened that night. However, her story has more than a few holes in it, including spending a couple hours having friendly drinks with Wo Fat (Mark Dacascos) who has returned to the island to kidnap and frame a Congressman and steal an election.
McGarrett and Danny (Scott Caan) are able to make a daring rescue of the Congressman who manages to escape his captor. Although Wo Fat gets away Five-0 is able to arrest his co-conspirator, the Congressman’s opponent (Greg Wrangler) in the upcoming election. And in the episode’s B-story Danny wins his court case for shared custody of Grace (Teilor Grubbs) and stops Rachel (Claire van der Boom) and Stan (Mark Deklin) from taking her daughter and moving to Las Vegas.