Trama

Cam apologizes to Zac for his betrayal but keeps the trident hidden. The girls look forward to returning to the pod. Everyone catches on to Cam's scheme and races to Mako Island. Will they stop Cam and be allowed to return to the pod?

Cam shows Nixie that he is hiding the trident in his school locker. Evie agrees to keep everyone's secret until after Zac is turned back into a normal human. Cam apologizes to Zac for betraying him. The girls look forward to returning to the pod. Sirena says a tearful goodbye to David. Cam lies to Evie about the mermaids' intentions. Everyone catches on to Cam's scheme and races to Mako Island. Will they succeed in stopping Cam and be allowed to return to the pod?—grrlpunk

Cam assures Nixie the trident is safe and shows it to her in his school locker. Satisfied, Nixie enjoys the thought that all their troubles will soon be behind them after the next full moon. Also looking ahead, Lyla and Sirena ask Rita to join them when they return to the pod but Rita turns down the offer, having made a life for herself on land. Zac explains his reason for lying to Evie who casts all the blame on the girls but agrees to keep his secret for one day. Sirena says goodbye to David who realises he will never see her again. Cam's manipulations continue as he tells Evie the mermaids will never turn Zac back to normal and that furthermore, the coming full moon will allow them to make his change permanent. Lyla overhears the entire conversation and tells Sirena and Nixie who reassures the others that Cam can be trusted. However, when Nixie attempts to show them the trident in Cam's locker to prove her point it is gone. Trident in hand, Cam makes his way to Mako Island to size the power of the trident for himself. Meanwhile, Evie warns Zac not to trust the girls and threatens to tell the world everything. When she explains the warning came from Cam, Zac realises what his friend has been up to and races to Mako Island to stop him. Having also realised her mistake in trusting Cam, Nixie and the girls collect Rita's Moon Rings and head to Mako as well. Zac confronts Cam and in their ensuing struggle, Zac is knocked unconscious giving Cam free access to the Moon Pool just as the full moon begins to rise high above Mako Island. Cam enters the Moon Pool the same way Zac did on the night of his transformation but Cam's fall into the pool is arrested mid-air by the girls who use their rings to keep him levitated above the water. As the power of the girls' rings begins to weaken under the stress, Cam descends closer and closer towards the water - and the power he so desperately seeks. Suddenly, Zac breaches up out of the Moon Pool and forces the trident from Cam's grasp, smashing it against the cave wall. As the full moon exits from view overhead, Cam is released and falls harmlessly into the water as the last power in the broken trident fades out. For saving the Moon Pool, Rita gives the girls their Moon Rings. Sirena returns to the café to see David. Zac tells Evie he's still a merman and Evie apologises to the girls. As Zac and the girls go out for a swim, Cam walks alone along the beach.

Cam assures Nixie the trident is safe and shows it to her in his school locker. Satisfied, Nixie enjoys the thought that all their troubles will soon be behind them after the next full moon. Also looking ahead, Lyla and Sirena ask Rita to join them when they return to the pod but Rita turns down the offer, having made a life for herself on land. Zac explains his reason for lying to Evie who casts all the blame on the girls but agrees to keep his secret for one day. Sirena says goodbye to David who realises he will never see her again.

Cam's manipulations continue as he tells Evie the mermaids will never turn Zac back to normal and that furthermore, the coming full moon will allow them to make his change permanent. Lyla overhears the entire conversation and tells Sirena and Nixie who reassures the others that Cam can be trusted. However, when Nixie attempts to show them the trident in Cam's locker to prove her point it is gone. Trident in hand, Cam makes his way to Mako Island to size the power of the trident for himself.

Meanwhile, Evie warns Zac not to trust the girls and threatens to tell the world everything. When she explains the warning came from Cam, Zac realises what his friend has been up to and races to Mako Island to stop him. Having also realised her mistake in trusting Cam, Nixie and the girls collect Rita's Moon Rings and head to Mako as well. Zac confronts Cam and in their ensuing struggle, Zac is knocked unconscious giving Cam free access to the Moon Pool just as the full moon begins to rise high above Mako Island.

Cam enters the Moon Pool the same way Zac did on the night of his transformation but Cam's fall into the pool is arrested mid-air by the girls who use their rings to keep him levitated above the water. As the power of the girls' rings begins to weaken under the stress, Cam descends closer and closer towards the water - and the power he so desperately seeks. Suddenly, Zac breaches up out of the Moon Pool and forces the trident from Cam's grasp, smashing it against the cave wall. As the full moon exits from view overhead, Cam is released and falls harmlessly into the water as the last power in the broken trident fades out.

For saving the Moon Pool, Rita gives the girls their Moon Rings. Sirena returns to the café to see David. Zac tells Evie he's still a merman and Evie apologises to the girls. As Zac and the girls go out for a swim, Cam walks alone along the beach...