Mako Mermaids: An H2O Adventure

Two young mermaids, Ondina and Mimmi, run away from the Mako Island pod with Sirena to try to turn merman Zac back into a land boy. But Zac's connection to Mako is growing stronger.

When Sirena insists that Mimmi and Ondina remove Evie's new mermaid tail, Mimmi reveals the astonishing range of her powers.

The mermaids use a moon ring on Zac to investigate his growing connection to Mako. As a result, Zac has visions of an ancient merman chamber on Mako, which he goes to explore, and the worried mermaids.

Erik is keen to get to know more about Ondina, but after accidentally transforming into a mermaid in front of Erik, Ondina is devastated. She pleads with Erik to keep the truth about her to himself, but Erik has a surprising secret of his own!

Zac and Erik enjoy their first swim together but are shocked to find Evie's Dad's boat at Mako, where he has begun taking dive tours. With their home under threat from tourists, Ondina warns Evie to stop her father.

Cam is on lifeguard duty when Erik quizzes him about Zac's connection to Mako. Erik is splashed and rushes into the ocean, disappearing. Cam paddles out in search of Erik, only to discover that Erik is a merman.

Zac goes on a camping trip to Mako with his father on the night of the full moon. Cam and Erik are invited too. Zac has another vision of the merman chamber, shared by Mimmi, who races to Mako with Ondina.

Mimmi's insatiable curiosity leads her to land school, where Erik quizzes her about the symbols he saw in the merman chamber, hoping she knows their meaning. Distracted by Erik, Carly accidentally spills a beaker of water on Mimmi and Rita.

Ondina reports back to the Mermaid Council but doesn't mention the existence of Erik, or that Evie now has a tail. She's followed home by a young, adoring mermaid, Neppy, who wants to help save Mako.

When Evie attempts to retrieve her father's watch from the marina's waters, David sees her tail. He's determined to prove mermaids exist and places cameras in the water, leaving the mermaids trapped on land.

Mimmi and Sirena prepare a potion that helps the user to look younger. Rita applies some before a school excursion to the Marine Park, accompanied by Dr. Ross, the park's handsome Director.

When Mimmi loses her moon ring in the Ocean Cafe's cooler room, it creates havoc for David and his brother's business.

On the night of the full moon, Zac is determined to discover the secrets of the merman chamber. Verida, the head of the Mermaid Council, arrives and uses her power to reveal that Zac was given up for adoption by none other than Mimmi's mother.