Rescue: HI-Surf

Captain Sonny Jennings and his core team of lifeguards monitor the dangerous Hawaiian waters; new lifeguard recruits compete to join Sonny's district; Sonny and his family grieve after the loss of his nephew; Em reveals a romantic past with Will.

A flash flood sweeps a young tourist away from her family and out to deep sea; going against Sonny's wishes, Em takes a bold risk and places her own life in danger in hopes of rescuing the lost-at-sea tourist.

Em works to earn the team's respect when she is left in charge. Hina and Kainalu juggle multiple beachside emergencies. Will's fiancé pays him a visit at work. Sonny opens up to a former lifeguard about his trauma since losing his nephew. Laka continues his flirtation with EMT Jenn.

A morning hangout on the beach almost turns deadly for a group of college kids when two of them get trapped in a collapsed sandpit. Meanwhile at sea, Sonny, Will, and Laka race to rescue people stranded after a shark attack. During a rescue, Em catches the attention of Fire Captain Sean Harimoto, and Will learns if he made the cut for the firefighter job he has been pursuing. Hina makes a move with Kainalu, and Sonny attends Zion's memorial fundraiser and attempts to reconnect with his sister for the first time since the funeral.
 

The lifeguards of the North Shore experience the most dangerous ocean conditions the district has seen in years; Sonny assigns Laka as acting lieutenant; Kainalu's father pressures him to leave his shift and help him with his campaign.

The swell has settled down, and the North Shore community comes together for Rocky's paddle out. Hina thinks about switching districts and Em tries to console her after the recent tragedy. Meanwhile, Laka, Will and Kainalu try to save a beachgoer that accidentally spears his own foot while fishing. Romance heats up between Sean and Em, and Sonny takes a personal day to go on a motorcross ride to clear his head, but ends up losing control.

Will, Laka and Em receive a call to rescue an influencer in a wedding dress that gets swept into the ocean while trying to film a new video. Kainalu and Hina discuss setting boundaries within their home, and Mayor Emerson makes good on his word with Captain Sonny. Meanwhile, Will breaks it to Em that his fiancé does not want her invited to their wedding, and Jenn finally agrees to go on a date with Laka.

Sonny, Em, Will and Laka race to the beach to find missing paragliders that plummeted into the ocean by a violent down draft. Kainalu invites Hina to a party with his ex-girlfriend and pretentious high school friends. Jenn doesn't think Laka is serious enough for her, and Em and Will face temptation of rekindling their past romance. Meanwhile, Sonny secretly puts in his notice to retire and recommends Em as his replacement.

Christmas cheer is in the air as the lifeguards prepare for their annual holiday toy drive. While surfing, a local grandpa has a heart attack and is rushed to the hospital, and Hina and Kainalu receive the responsibility of babysitting his grandkids. Sonny tells Laka he is not ready to become a lieutenant, and Laka does not take the news well and spirals at a bar. Chief wants Kenji to replace Sonny as Captain, but Sonny is stern on recommending Em and calls in a final favor with Mayor Emerson. Meanwhile, Will and Em almost get caught in the act by friends, and Hina and Kainalu become more than roommates.