The heat's on as the 'Hawaii Five-0' team takes on some of the Aloha State's most notorious and baffling criminal cases involving murder, the Mob, espionage, and kidnapping. With McGarrett (Alex O'Loughlin) and Danny (Scott Caan) at the helm, the team interrogates members of a renegade stunt-bikers gang, pursues a rogue Russian spy with access to NSA secrets, and partners with a autistic child in a murder investigation. Chin (Daniel Dae Kim) and Kono (Grace Park) are held at gunpoint by two killers who don't know they're cops, and Grover (Chi McBride) - and his family - are haunted by a 15-year-old Mob investigation. Meanwhile, Catherine (Michelle Borth) returns to the islands and McGarrett prepares to take their relationship to the next level. Season 6 is 25 high-caliber episodes that prove, once and for all, that crime definitely does not pay.