Zac Blakley, Portrayed by Chai Romruen, is a high school student who under a full moon receives the gift of being a merman. Along the way, Zac discovers how to use his powers and the greatness that comes with it.
Portrayed by Dominic Deutscher, Cam Mitchell is an amusing and clumsy land boy who also happens to be Zac's best friend. Since the very beginning Cam has known all about the mermaids and of course Zac - a merman.
Portayed by , Ondina is a pod mermaid who at times may seem a little arrogant but in the end will do whatever it takes to save the pod. Ondina finds herself on land where she is forced to 'wear' legs until they have accomplished the mission of turning Zac back into a normal landboy with no relations to being a merman but during the second season they find a startling twist to the story
Hard working and easy going Evie McLaren, portrayed by Gemma Forsyth, is a kind and fun loving girl who soon discovers the magic that lies beneath the sea. Until the second season Evie is your normle everyday 'land girl'. She is dependable and likeable and a good friend who you can count on no matter what!
Portrayed by Amy Ruffle, Sirena is a pod mermaid who first came to land to discover more about they merman Zac, along with her she brings Nixie and Lyla, Ivy Latimer and Lucy Fry, two mermaids from the same pod as Sirena. The three discover how Zac isn't so bad and can be trusted.
Portrayed by , Mimmi is a kind and comforting pod mermaid, originally from the northern pod and finds herself in the same position as Ondina, she will do whatever it takes to save the pod.
Portrayed By Brooke Nicole Lee, Carly Morgan, Evie's best friend, cheerful, couragious and brave land girl who only discovers about the sea and what lies beneath in the late second season. Carly recieves a horrible fright soon discovering her best friend she has known for almost half of her life hasn't told her about one of the most amazing changes Evie has had that involves water and touching it.
Rita Santos, portrayed by Kerith Atkinson, is the Principal at Suncoast high, the high school where Evie, Cam, Carly, Zac and others go to. Not only is Rita a high school teacher but also a mother figure and guardian for the pod mermaids. Of all people, Rita is the one you would go to for advice.