This article is about the first season of the H2O: Mermaid Adventures series. You may be looking for the first season of H2O: Just Add Water, which can be found here, or the first season of Mako: Island of Secrets, which can be found here.
Three girls named Emma Gilbert, Cleo Sertori and Rikki Chadwick, who were regular girls. With the suggestion of Lewis, they go out to a skin diving trip at Mako Island to help Cleo learn more about ocean creatures and get her job at the Oceanic Center.
After they're discover the motor on their boat gets flooded and with no signal to make any phone calls, they get stuck on the island, waiting to be rescued. The girls find it hard to sleep with Lewis snoring, and wander towards a glowing cave, hoping someone is there. Each of the girls fall down a a tunnel in the cave, but find it impossible to escape without swimming. Before they can leave, the pool glows and bubbles, transforming each of the girls' legs into tails.
Trivia[]
- This season is split into two seasons with each 13 episodes on Netflix.
- Due of being an adaptation of H2O: Just Add Water, some episodes are likely inspired by its live-action counterpart.
Episodes[]
| Image | Title | Original Airdate | Episode | ||
|---|---|---|---|---|---|
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The Secret of Mako Island | May 22, 2015 | 01 | 1.01 | |
| Cleo, Emma and Rikki get stranded on Mako Island and fall into a magic pool where their lives change forever. | |||||
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Caught in the Net | May 22, 2015 | 02 | 1.02 | |
| Emma competes in a contest, Cleo is stuck babysitting an intern and save an injured sea turtle. | |||||
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The White Mermaid | May 22, 2015 | 03 | 1.03 | |
| The girls discover of an ancient mermaid statue and return it but treasure hunters have another idea. | |||||
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A Stormy Party | May 22, 2015 | 04 | 1.04 | |
| A storm threatens to wash out a birthday party. | |||||
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Mako Island Hotel | May 22, 2015 | 05 | 1.05 | |
| Zane's father plans a luxury resort on Mako Island. | |||||
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The Mysterious Seaweed | May 22, 2015 | 06 | 1.06 | |
| Aggressive blue seaweed attacks Emma. | |||||
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It's in the Bag! | May 22, 2015 | 07 | 1.07 | |
| Discarded plastic bags pose a threat to Teddy and his friends. | |||||
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Dolphin City Triangle | May 22, 2015 | 08 | 1.08 | |
| Atmospheric disturbances result in disastrous consequences. | |||||
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Poseidon's Daughter | May 22, 2015 | 09 | 1.09 | |
| Dolphin City is the location for a new movie. | |||||
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Dolphin City Mascot | May 22, 2015 | 10 | 1.10 | |
| Danny gets captured by the Oceanic Center for observation. | |||||
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Bad Waves | May 22, 2015 | 11 | 1.11 | |
| Lewis and the girls must find what's behind mysterious sound waves that are creating havoc. | |||||
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Jaws-ache! | May 22, 2015 | 12 | 1.12 | |
| Burke breaks a tooth and wanders near the beach in pain, causing a panic. | |||||
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The Lost Ring | May 22, 2015 | 13 | 1.13 | |
| Rikki takes matters into her own hands by spying on her dad and his new girlfriend. | |||||
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Reported Missing | July 15, 2015 | 14 | 1.14 | |
| Clown fish begin to vanish, so the girls investigate why this is happening. | |||||
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Memory Lapse | July 15, 2015 | 15 | 1.15 | |
| Cleo forgets about her ability to change into a mermaid, so Emma and Rikki must make sure she doesn't transform in public. | |||||
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Valentine's Day | July 15, 2015 | 16 | 1.16 | |
| Lewis wants to share a big secret with Abby on Valentine's Day, and Cleo worries that he will tell her about the girls' mermaid identities. | |||||
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Kidnapped! | July 15, 2015 | 17 | 1.17 | |
| Bobbie's twin brother gets abducted by someone in a curious speedboat. | |||||
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A Strange Phenomenon | July 15, 2015 | 18 | 1.18 | |
| Cleo has some powerful nightmares after her father goes to sea on a mission. | |||||
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Handle With Care | July 15, 2015 | 19 | 1.19 | |
| Tired of the racket Miriam and Zane are making at their beach party, Bernie leaves his cave -- giving the Vandals a chance to move right in. | |||||
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The Return of the White Mermaid | July 15, 2015 | 20 | 1.20 | |
| To protect the White Mermaid, the girls guide explorer Stanley Finch to the underwater Stone Circle, whose magic makes Stanley think he's a pirate. | |||||
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Three Days Underwater | July 15, 2015 | 21 | 1.21 | |
| When a spell forces Rikki to remain a mermaid until the next full moon, she has to find a way to lay low -- and underwater -- for three full days. | |||||
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Robot Duel | July 15, 2015 | 22 | 1.22 | |
| Lewis is thrilled when the university hosts an underwater robot competition, but the girls fret over the safety of their marine friends. | |||||
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The Creature From The Bay | July 15, 2015 | 23 | 1.23 | |
| Emma's younger brother catches a glimpse of her mermaid tail and thinks he's seen a sea monster -- soon the whole town is in an uproar. | |||||
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Underwater Takeover | July 15, 2015 | 24 | 1.24 | |
| The mermaids turn to a cranky giant octopus for help when the Vandals invade the bay with a horde of stinging jellyfish. | |||||
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Imminent Danger | July 15, 2015 | 25 | 1.25 | |
| Having played one too many practical jokes, Teddy can't get anyone to believe his warning that an underwater volcano is about to erupt. | |||||
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Trapped | July 15, 2015 | 26 | 1.26 | |
| Lewis joins a famous explorer in a high-tech submarine to hunt for a sunken treasure ship, but a mishap strands them at the bottom of the sea. | |||||