The team investigates a centuries-old pirate story involving buried treasure; Gabriel kidnaps Kono and Adam on the morning after their wedding.
A bomb squad is attacked and the culprit threatens to detonate hidden explosive devices unless arsonist Jason Sinclair (Randy Couture) is released from prison.
A scuba diver is killed with a gun that was used in a recent murder; McGarrett gets ready to propose to Catherine.
A wealthy recluse's corpse is found in a field with almost $1 million in counterfeit bills; Adam is abducted and forced to torture one of Gabriel's men.
The team questions members of a stunt biker gang when a killer escapes by jumping his motorcycle from roof to roof; the team prepares for Tough Mudder.
On Halloween, the team tracks a serial killer inspired by an iconic character; a blood bank is raided by an armed gang.
Alex O'Loughlin
Steve McGarrett
Scott Caan
Danny "Danno" Williams
Chi McBride
Lou Grover
Jorge Garcia
Jerry Ortega
Meaghan Rath
Tani Rey