Lives in Zac's Garage
Mimmi (biological sister)
Good looking and charming, Zac starts out as an all-round nice guy. When interviewed, Chai reveals that Zac is a very strong character, but he also has a soft side. He's popular and sporty, and always off on an adventure with his best friend Cam. The two have a healthy and long-running rivalry, which fuels both boys in everything they do - and they banter constantly, but they are essentially equals. That is until the Moon Pool endows Zac with amazing powers and the ability to morph into a merman with amazing powers.
When he first gets a tail, Zac experiences a range of different emotions. First he's plain stunned, then intrigued, then bummed - after all, his new status as half-fish undeniably makes him a bit of a freak. In addition, he knows he can't get wet in front of people without morphing - and that would be a disaster. But he soon finds out the perks of his powers outweigh the negatives, and starts to embrace his new identity. This causes a rift in his friendship with Cam - who is used to being Zac's equal and is possibly jealous of his merman abilities.
When things hit rock bottom with Cam, Sirena, Lyla and Nixie learn of Zac's powers and Zac finds a new support network. It's Lyla that Zac feels most comfortable confiding in, causing problems with his girlfriend, Evie. This all changes when Zac discovers not only is Lyla a mermaid - but she wants to take his amazing new powers. The battlelines are drawn.
Zac possesses the ability to transform into a merman ten seconds after touching water.
As a merman, he has the ability to swim at super speed of 600km/h, hold his breath for at least 20 minutes, and dive at a depth lower than the deepest divers in the world. After drying, his body reverts back to human form.
In "Dolphin Tale", he starts the ignition on Joe's boat and starts moving it. In "Zac's Return to Mako", when he was under the influence of the Full Moon, Lyla tried to stop him from reaching the land entrance and he pushed her using this power.
After his first Full Moon in "Zac's Return to Mako", he is now able to become invisible like the girls. In "The Siren" Zac turns invisible so Mrs. Santos doesn't see him in her office. In "Truce" and "Nowhere to Hide" he uses this power so he doesn't caught in the cafe and the warehouse.
Zac used this power to improve Cam's and Carly's singing in "Sirena's Secret".
Zac is very fond of Evie and cares very much for her and wants to be a good boyfriend. Their relationship becomes very strained because of Zac hiding his secret from her, and even more when Lyla and Zac become close friends. Evie is the one person he does not want to discover his merman side for fear of losing her. She later finds out to her amazement about his tail when he is forced to save her from drowning in "Betrayed"
Zac and Cam have been best mates from the time they were young children. At first Cam is very supportive of his friend and helps him keep his secret hidden from Evie. Until "Zac's Pool Party" when Cam get tired of covering for him and shoves him into his pool, Zac's secret exposed to the three undercover mermaids. Later, they make up and Cam starts helping Zac to get the trident. Later, Cam grows even more jealous of his friends powers and is outraged when Zac puts the trident back into its chamber. Finally, He schemes to become a merman, but is unsuccesful and in the end is on his own.
Zac's girlfriend Evie gets jealous of Lyla after seeing them 'cuddling' on the jetty. Lyla and Zac become really close after she and the other two mermaids 'accidentally' discover he is a merman. Zac always feels the most comfortable around Lyla and they form a very close bond. Zac may yet discover he has feelings for her later on. For more on their relationship go to - Zac and Lyla
She is Zac's sister. During the seventh cycle Zac began to have visions of Mako Island, and the trident chamber along with Mimmi who is able to see them as well. Rita finally revealed that Zac is Nerissa's son, and Mimmi's brother due to Zac, and Mimmi able to share visions from their bloodline. He couldn't accept Mimmi as his sister or the truth of his bloodline. They share a mind connection unlike noneother as much as Zac denies her as his blood-sister.
The image gallery for Zac may be viewed here. .