h2o: Just Add Water is the awesomest show ever! Starring are Phoebe Tonkin as Cleo Sertori, Claire Holt as Emma Gilbert, and Cariba Heine as Rikki Chadwick. The summary is that Cleo, Emma and Rikki become mermaids on Mako Island and after that, after they make contact with water, they turn into mermaids with powers after 10 seconds. Cleo can mold and move water, Emma can freeze water, and Rikki can boil water all with just a slight hand motion.
Later on, Emma leaves h2o to film in a different movie in Season 3, while Indiana Evans, who stars as Isabella, or Bella Hartley comes in to take Emma's place as a mermaid who can turn water into jelly. She became a mermaid in the caves of Ireland, as she explains later on.
The girls fight through Seasons 1-3 to make sure they are not discovered and dissected, put on display, or in a circus. However, they are discovered by their later boyfriends, Angus McLaren, who stars as Lewis McCartney a science geek, the girl's friends and Cleo's later boyfriend. He discovers they are mermaids at a pool party. Burgess Abernethy, who stars as Zane Bennett a rich local bad boy, is later on Rikki's boyfriend and he discovers they are mermaids at the end of Season 1. Craig Horner, who stars as Ash Dove a horse ride trainer and manger of the Juicenet Cafe, is later on Emma's boyfriend and he finds out they are mermaids at the end of Season 2. And Luke Mitchell, who stars as Will Benjamin a professional diver, is later on Bella's boyfriend in Season 3. He discovers they are a mermaid in the middle of Season 3. Together, they share the girl's secret through the entire show.