During the first week of autumn at Baywatch with Hobie gone away to college and heavy rainfall in the area, Mitch discovers that his shipboard marriage to Neely is invalid, which worsens things then Neely's ex-husband suddenly shows up with no knowledge of Neely's baby or anything else making Mitch realise that Neely lied to him all this time and she has fully reverted back to her conniving and devious true self.

Mitch, Craig, Neely, J.D. and Newman co-operate with the Coast Guard in rescuing as many people as possible from the waters of the plane crash and fending off shark attacks as well.

Mitch deals with Captain Alexis "Alex" Ryker, the conniving CEO of a private lifeguard company called Bayguard, who wants to take over the Baywatch lifeguard company to expand her company. When Mitch suspects Alex of setting up rescues to appease Chief Johnson, he resorts to having Cody spy on the Bayguard team to uncover any underhandedness.

Cody accompanies Alex on a vacation to Hawaii where she wants to spend time with her autistic 10-year-old nephew, Timmy, and to show him to swim with dolphins in the local lagoon, which the mute Timmy is afraid to do so.

A mysterious figure called "The Phantom Lifeguard," begins making rescues and disappears before being identified by anyone. While Mitch thinks the Phantom Lifeguard is an outsider, Cody and J.D. think the unseen hero of the day is getting his/her information from inside the department.

April mentally falls apart after losing a rescue, while Mitch and the grieving widow refuse to give up searching for the body.

Hobie takes out his wild and crazy college friends for a boat trip while under the influence of alcohol and they all end up in a boating accident in which Hobie's girlfriend falls into a coma and leads to Hobie being arrested and facing charges of manslaughter.

Mitch befriends Tanner, an abused nine-year old boy who tries out for the junior lifeguards in order to get away from his ill-tempered, alcoholic, divorced father, Blake. But Mitch feels helpless in helping Tanner when everyone tells Mitch not to get involved in the boy's troubled home life and to mind his own business. Things turn chaotic when a bus falls off a bridge and lands in 20 feet of water.

Mitch, feeling that his life has reached a midpoint from his failed marriage to the absent Neely, goes for a day-long tower swim along the beach and encounters various other problems which include, April and Craig's growing attraction for one another, and reluctant heroes Cody and J.D. refusing to take the credit for saving two girls and a pair of policemen after falling off a pier.

Mitch takes in an orangutan, named Morton, that escapes from it's abusive dwarf owner which complicates Mitch's and Alex's plans for Baywatch's annual Special Olympics program, while Cody and Jessie deal with Morton's owner, Herbert Green. One of the Special Olympics participators, a hearing-impaired girl named Kara, takes a liking to Morton and when she tries to hide Morton from Herbert, they end up trapped in a cave with a rising tide that threatens to drown her and the orangutan.

Cody puts his career (and life) on the line when he starts using a performance-enhancing supplement in hopes of making it to the 2000 Sydney Olympics, which soon begins affecting his life guarding job as well.

Mitch becomes acquainted with some old armed service friends of an Army parachutist team where he tries to reunite one sky jumper, Tracy McComb, with her estranged Naval officer father who has a terminal illness. Jessie becomes intrigued with skydiving and persuades Mitch to go along with her for a jump, which takes a turn when they are forced to rescue some people from a boat wreck off Catalina.

Mitch finds himself on the wrong side of the law when he becomes reacquainted with Tanner, the abused nine-year-old boy, whom he snatches away from his abusive father, Blake, and lets the boy stay at his house while Alex becomes Mitch's co-conspirator in helping Tanner.

Craig tells Mitch a shocking secret that he has lymphoma when they become caught up in a high-risk adventure at sea starting when they get lost in a fog while paddle boarding and then get attacked by a shark. They manage to reach land only to end up as prisoners on a top secret military test range. Back at Baywatch, April cannot find the right time to tell Manny about her involvement with Craig.

Mitch gets the need for speed when Tanner's cousin Damon Lusk, a race car driver, visits for a race car competition, and who also has a meeting of the minds with Alex. But when Damon falls ill due to food poisoning, he asks Mitch to take his place for a major grand prix race, where Mitch comes up against an old rival from his own former race car days.

Mitch's Zuma Beach lifeguard friend, Jake Barnes, learns that his Australian ex-wife has suddenly died. So he, Mitch, Alex, April, Cody, and Jessie go on a trip to Australia where Jake is to meet the eight-year-old son, Terry, that he never knew. Upon arrival, Jake with Jessie in tow, travel to the Avalon Beach Resort Club where Jake meets with Terry and his ex-wife's friend Allie Reese, a helicopter pilot and lifeguard at the beach club, where Jake and Terry seem to hit it off.

While Mitch, Alex, Cody, and April prepare for their race against the Australian lifeguards, Jake must choose between staying in Australia with Terry or returning home without him. But when Terry does not want to leave Australia, he goes missing which prompts Jake, Jessie, and Allie to look for him.

Having received a Dear John-type letter from Lani saying that she has moved on and is now romantically involved with someone else in New York, Cody gets a lesson in love when he and Mitch help out a brilliant, but troubled, violinist named Ariana to get away from Lena, her dangerous and overbearing trainer with a secret agenda.

While on her way to her grandmother's birthday party, Alex's day gets sidetracked when she tries to save a diamond runner, named Ben, whose partners, Lisa and Jason, want to silence him for good which leads to a standoff in an underwater cave with Alex and Ben trying to avoid the rising tide and the smugglers circling above in their motorboat.

April tries to save Manny from himself after he suffers a life-altering back injury during a rescue. April then decides to take Manny's place with Hobie in a boat race with the other lifeguards from Baywatch.

April and Jessie search for the perfect celebrity host the Miss Galaxy Beauty contest Baywatch is sponsoring, when they stumble across and get duped by a con artist impersonator, called Earl, who claims to be the real George Hamilton.

A frantic weekend begins for Alex when she begins tracking down the builder of several elaborate sand castles that appear every day at the beach, while she gets stuck entertaining her life-long childhood friend Sam's fiance, Diana, who falls for Mitch, which prompts Mitch to asks Alex to pose as his girlfriend to keep Diana away.

Mitch Bucannon, on leave in Oahu, Hawaii while he sorts out his thoughts during a mid-life crisis (his failed romance with Neely, his mother's recent death, and Hobie living on the East Coast), decides to form an international team of lifeguards in Hawaii called 'Baywatch Hawaii' for saving lives after a rescue of a family on a remote beach in which a little girl is put in a coma after being submerged.

During the first week of training for the new lifeguard team of Baywatch Hawaii, competition between Jessie and Kekoa, as well as Jason and J.D. threaten to turn the tryouts into an all-out war. Jason, at Kekoa's advice, visits an old Hawaiian native to look into his true Hawaiian roots, and Allie takes a job as a helicopter tour pilot to make some extra money for herself.

Dawn Masterson, a lifeguard from Florida and a travelling archaeologist, joins the team and proves almost irresistible to the male lifeguards while she squares off against Sean who tries to find her weakness, while also Dawn seeks her own personal agenda with J.D. whom she used to know.

Mitch takes Tanner on an overnight camping trip to a small island where a dream encounter with a ghostly Hawaiian drives Tanner to deal with his inner conflicts from his troubled life back in Los Angeles.

Sean and the rest of the team risk their lives when they help with the local Coast Guard in a daring rescue to save six kaiakers who have gotten stranded on Kauai's Pina Nova coast. After saving four of the kaiakers, including two in an enclosed lagoon, night falls and the search for the remaining two is called off.

The abrasive Sean tries to get the team, on a week-long holiday in Kauai, from giving into the island's sun-and-fun atmosphere and concentrate on a return to training.

After Jason risks his life in a rash attempt to save two scuba divers trapped on a reef, Sean threatens to throw Jason off the team if he doesn't change the way he thinks about the risks and lives of people in need of a rescue in which Jason is confined to a beach for the whole day to learn what the people that are there are confronted, with Sean keeping a close eye on him.

Mitch struggles to prevent Hobie from marrying his new girlfriend, Sarah, at a local hotel during a visit, while Mitch also deals with Sarah's overbearing and obnoxious parents seeking to create the perfect wedding.

Sean, Allie, J.D., Jason and the rest of the team race to help Jessie as she faces the challenge of her career when she rashly attempts to track down a pair of shark hunters who are decimating the animals in the Hawaiian area.

During a girls swim out in the ocean, Allie discovers a rare gold coin dating back to a ship that was lost in 1941 during World War II which allegedly contains un-circulated gold coins and rare artifacts somewhere off the Hawaiian coast.

Allie's relationship with Nick begins to heat up, especially after he suggests a commitment between them. Then things take a turn when Allie, Nick and the rest of the team must cooperate with the Coast Guard to rescue two people trapped on a disabled submarine 200 feet on the ocean floor.

A secret from Dawn's past could jeopardise her position on the team when she gets served with a civil suit from the spouse of a diseased lifeguard from when she was involved in a failed rescue while working as a lifeguard years ago in Florida with J.D.

After a rescue of a man who survived after more than 20 minutes underwater, Dawn and Sean are drawn to the strange and spiritual power of the mind over matter theory which she tries to prove the theory of the mind controlling the body after its other functions have shut down to sustain life.

Sean has his hands full in dealing with Jenna Avid, the new head of the Oahu North Shore lifeguards, who issues some stern recommendations to the team, which is overshadowed later that day when a group of nudist activists, lead by a certain Leesa Strickler, choose the beach near the Baywatch Hawaii headquarters as their place of protest against the establishment which Sean, Jason, Allie, and Dawn have also deal with the media circus that arrives too.

Sean faces a personal conflict where he tries to resist Kekola's flirting advances which leads her, Dawn and Allie to re-examine their own femininity in themselves.

Sean sends Jason to the big island of Hawaii to meets with Kulu Puno, an elderly Hawaiian and his beautiful young granddaughter where Jason is given a task of building an old fashion Hawaiian canoe as part of a path he must see to redeem himself from his arrogant, immature nature.

During a long day when Sean takes Jenna out on a Scarab motorboat when after a rescue of a injured young boy from a offshore reef, Sean reveals a secret to Jenna that could threaten his position when he tells her about his own son, that no one knows about, who drowned years ago which ruined his life and paved his way to becoming a lifeguard.

Jessie tries to overcome her physical condition, and Sean's objections, to compete in a Maui triathlon with Dawn as her personal coach while Allie suspects an agenda behind Dawn's motives to train Jessie.

Sean tries to keep his blossoming relationship with Jenna a secret to avoid upset and criticism from the rest of the team when he attends a lifeguard conference on Maui to speak about the dangers of drowning where Jenna, Allie, Kekoa, Dawn, and Jason are in attendance.

Mitch helps Jessie try to prevent her World War II veteran grandfather from committing suicide who was a survivor from the USS Utah at Pearl Harbour and who harbours a guilt over surviving when many of his friends didn't on December 7, 1941.

Mitch is asked by a government agent to investigate a certain Zack Martin, a former Navy SEAL who may be part of an environmental terrorist group called "Green Scorpion" who are planing to blow up an unknown target.

Another long day begins with Sean, Jessie, and Kekola trying to save a woman trapped in an air pocket beneath a coral reef and trying to escape from the dangerous sulphur fumes within the cave. After a rescue of three skydivers whose parachutes open late, Dawn find a number of similarities between one named Jerome, and her ex boyfriend Ryan whom she discovers that they are both the same person.