Who Played Steve McGarrett on Hawaii Five-O

Steve McGarrett is the determined former Navy officer turned Honolulu police commander who leads the elite Five-0 Task Force. On the original Hawaii Five-O (1968–1980), the role was originated by Jack Lord, who shaped the character’s stoic authority and became synonymous with the franchise. In the 2010 reboot (2010–2020), the character was reimagined with Alex O’Loughlin as the brooding, modernized leader of the task force. Below is a verified breakdown of each portrayal, including production context and defining traits to clarify credits and enduring fan perceptions.