Surf, why it's the most demanding job he's done, working with Arielle Kebbel, the water scenes, and the season finale.

Oahu’s North Shore lifeguards are fearless except when it comes to their own hearts. That’s especially true of Lieutenant Em ...

Arielle Kebbel: They are like magnets to each other ... Em is asked to leave her job [temporarily] and run water safety for a very wealthy person on their yacht across the Pacific.

We talked to Kebbel about their on-again, off-again relationship – and how assisting in a real-life rescue helped her understand the unbreakable bond that first responders share.