<sod> |ShortSummary = Five-0 investigates a Russian spy that stole a flash drive full of top secret information. Meanwhile, McGarrett learns why Catherine left and Abby continues her secret invention into the Five-0 task force. <eod>
<sod> |ShortSummary = Five-0 investigates the murders of two hospital surgeons and the patient they were about to operate on. They determine that the patient was the real target, as Max shows them X-Rays where a small object was embedded in his skin recently. The vic was actually a mule, carrying a flash drive to Hong Kong for someone else, Chris Dalton, an NSA employee. Dalton's girlfriend, Anna Novick, is the killer, as she is a Russian spy. Five-0, HPD, and SWAT surround Dalton and Anna, but Anna calls for backup to attack Five-0 while she and Dalton escape. However, Dalton slips away from her and is captured by Five-0. At headquarters, Dalton reveals the drive contains the identity of undercover spec ops around the world. Dalton's boss comes to Five-0 and informs McGarrett that his name came up in relation with one of the operatives they can't reach: Catherine Rollins. McGarrett and Danny attempt to make sure that Dalton's encryption in the flash drive is secure and that Anna can't unlock it without him. However, Anna pumps nerve gas through the air ducts or Iolani Palace, knocking everyone out. She kidnaps Dalton and takes him to a safe house where she forces Dalton to unlock the drive. McGarrett and the team storm the house and retrieve the drive. As Anna is arrested, McGarrett reveals to Danny that he is angry that Catherine lied to him again, but at the same time he understands why she did it. Meanwhile, Danny returns from New Jersey and informs the rest of the team that the man after them is Robert Coughlin, Rex Coughlin's brother. Chin and Grover relate Rex's history to Abby: that he tried to bring Chin down on anything and even struck a deal with Gabriel Waincroft to do it. They believe that Robert is after them because of Rex's death. Abby informs Robert that she doesn't think Five-0 is corrupt, but she is told to get something on Five-0 and stay undercover or she'll be fired. At the end of the episode, Abby confesses to Chin who she really is and why she's really there.<eod>