Charlotte Watsford is one of the secondary characters in Season 2 of H2O: Just Add Water. Charlotte is the main antagonist of Season 2, predominantly after she became a mermaid. Charlotte is the granddaughter of former mermaid Gracie, and is the daughter of Annette Watsford. She attended the same school as Cleo, Lewis, Emma and Rikki during Season Two.


Charlotte is the new girl in town and arrives after the girls were given their new powers. She has a passion for art, and grew an attraction to drawing Mako Island. At her old school of Rosewood Secondary College she was one of the best artists. She also has a sudden crush on Lewis, who was initially Cleo's boyfriend. She draws a picture of him, after Cleo claims she needs space to learn to control her new powers, and uses this time to try to get Lewis to go out with her. In "Missed the Boat", Charlotte comes up with a plan to get Lewis alone, away from Cleo. Following Cleo's poor exam results, Charlotte takes it upon herself to tutor Cleo, forcing Cleo to study at home, while Charlotte gets Lewis to take her to Mako Island. This allows her to kiss Lewis at Mako, forming their relationship.

Becoming A Mermaid

Charlotte finds a picture of her grandmother at Sertori's House. After that she starts to get suspicious of Lewis and the girls. This leads Charlotte to secretly break into Cleo's room and steal a film, in which she would discover the existence of mermaids, and that her own grandmother was one. She confronts Lewis with this information, only to end in him denying their existence. In "Then There Were Four," Lewis, in an attempt to give the mermaid research back to Max Hamilton, Charlotte secretly follows Lewis and asks Max questions about Gracie.

Max confirmed Charlotte's suspicions that Gracie used to be a one of the original mermaids. Max tells Charlotte, that although Gracie was a mermaid, he still loved her, and even more so when she was a mermaid. This may have influenced Charlotte into becoming a mermaid, so that Lewis would love her more than Cleo. Charlotte asks Max "How did this happen?" to which Max responded with "In the right place, at the right time, magic happens." After arguing with Lewis once again, Charlotte runs off and reviews the film of Gracie's transformation, and determines that Mako Island's Moon Pool could be where the 'magic happens'. She takes a boat and travels to Mako Island, where she goes to the Moon Pool.

Charlotte then discovers that Cleo, Emma and Rikki are mermaids, and overhears them mention "the moon". Once the full moon is up, Charlotte recalls Max's words that this was the 'right place', and the 'right time' for the magic to happen, Charlotte proceeds to jump into the moon pool and becomes the fourth mermaid. The next day, Lewis is ready to make amends with Charlotte, and meets her on the jetty. She calls Lewis out for being full of secrets, but that he needn't worry anymore. Charlotte then dives into the water and transforms into a mermaid. She arises extremely happy, asking a shocked Lewis "isn't this fantastic?!"

The "Super Mermaid"

Once Charlotte becomes a mermaid, her true colors come out and the girls don't take her in so well. She initially tries to find out what her powers are, but fails. After a while, she finds out that she has Cleo's power, then Rikki's powers and Emma's powers. This causes her to believe that being a mermaid was meant to happen to her. She titles herself as a "Super Mermaid" and a better mermaid than the other girls, this is due to her mastering her powers faster than the other girls, and having control over all the elements, making her the most powerful mermaid in the entire series. However, this leads to Charlotte becoming egotistical and power hungry.

After a power fight between Charlotte and the other girls over Nate when he attacks Lewis and tries to steal his boat, she stops collaborating with the girls, and starts practicing her powers her own way. At Lewis' birthday party, Charlotte locks Cleo and Emma inside her pool room by freezing the lock shut, and uses hydrokinesis to burst a pipe full of water all over the girls, transforming them into mermaids. Rikki manages to rescue Cleo and Emma by using her powers to free them. This leads Cleo and Emma to backlash against Charlotte, essentially ending their brief friendship. Charlotte in return tells Lewis that he is no longer allowed to talk to the girls, especially Cleo.

Charlotte decides to bully Cleo with her powers. "And you call yourself a mermaid, you're pathetic." Furthermore, Charlotte rips Cleo's locket off of her neck, feeling that it was rightfully hers, since it belonged to her grandmother. Cleo, who is extremely upset, after losing her locket and her friendship with Lewis, and additionally feeling that Lewis doesn't care even a little for her anymore, she runs off to the sea. When Lewis finds that Charlotte has bullied Cleo, and has stolen her locket, he is disgusted and finally breaks up with Charlotte for good and goes off searching for Cleo, ultimately resulting in Lewis and Cleo getting back together as a couple. Charlotte, now bitter and heartbroken, deals with her anger of being dumped by abusing her powers on the girls, after they attempted to warn her of the full moon. Charlotte arrogantly ignores them, after stating that she is the most powerful mermaid, even more powerful than all three of the girls combined, and proceeds to use her power of aerokinesis to push them into the air until Ash comes out, reluctantly forcing her to drop them.

Losing Her Tail

That night Charlotte intentionally walked outside and looked at the full moon, placing herself under a moonspell trance. On this night, the planets were all aligned with the full moon, which only occurs every fifty years. This occurrence can draw away the powers of any mermaid in the moon pool when the full moon passes over, forever. (This was how Gracie lost her powers, along with the other original mermaids, Louise and Julia). Charlotte, under the moon's spell, caused chaos at Emma's house by using her powers to try lure to out the girls to travel to Mako Island, with the trio being unable to retaliate since Ash was in the house, and additionally using Lewis as bait. Lewis, however, also tried setting up his own trap to remove Charlotte's powers from her by luring her to the moon pool. At the same time, Charlotte wanted to take away the girls powers so that she could be the most powerful mermaid ever, and so that she would be the only special one for Lewis.  

Once luring Cleo, Emma and Rikki to the moon pool, the four mermaids engage each other in a fierce power battle, where Charlotte created a three-headed water elemental snake to attack the girls. However the girls destroy the snake with a powerful electric storm. In one final power fight, Charlotte gets overwhelmed by the girls' Combined Atmokinesis; the very power the girls obtained just before Charlotte arrived in town, and results in the most powerful mermaid being dropped into the moon pool, and stripping Charlotte of all of her powers, forever. Charlotte attempts to win Lewis back, or else explain her motivations behind becoming a mermaid for him (she said that all she wanted was for him to care for her), but, though Lewis understands her motivations, she is unsuccessful, and is forced by Lewis, to return Cleo's Locket, and in doing so, she indirectly promises to never tell anyone about mermaids. Since losing her tail, the locket, and Lewis, Charlotte is thought to have moved away in shame and despair, broken by her defeat. 


Charlotte appeared in Season 2, but was not introduced until the second episode, after the girls got their advanced powers. Charlotte was also absent for the episode "Moonstruck." Charlotte is completely absent from the show after Season 2 and was never seen or mentioned again.


Charlotte is a teenage girl, her hair is mid length and dark red in color. Charlotte is medium weight, and is tall in height. She has a rounder face structure but has a clear skin complexion with no blemishes. She is seen wearing conservative clothing that are usually in different colors. Charlotte temporarily used to wear her grandmother's locket that she stole from Cleo, but at the end of Season Two she unintentionally gave it back to her. As a former mermaid, Charlotte's hair was let down and she had an orange-scaled tail with a matching orange-scaled top.

Mermaid Powers

Charlotte formerly possessed the ability to transform into a mermaid ten seconds after physical contact of water. Once her body is completely dry, she turns back into a human along with the outfit she was wearing before she transformed. As a mermaid, Charlotte once possessed the ability to swim at a super speed, and dive at depths no human being is capable of, completely protected from its cold and water pressure. She was also capable of holding her breath for at least fifteen minutes.

At the time of her transformation at the Moon Pool of Mako Island, Charlotte was alone, and by standard, she was gifted with all the regular and weather powers. This was the fact that made her think she was a "Super Mermaid", claiming she was more mermaid than Cleo, Emma and Rikki themselves, thinking they were less powerful than her. However, this was false, because when they combined their powers at the night of the Moon of Fifty Years, Charlotte was deprived of her tail and all of her powers were gone, and she returned to being a human once again.


Before her transformation, Charlotte had all the typical weaknesses of a human. When she transformed, she was susceptible to all the weaknesses of a mermaid. Being deprived of her tail and abilities permanently, Charlotte had again all the weaknesses of a human.

Behind the Scenes

She was portrayed by actress Brittany Byrnes.


  • Charlotte is afraid of dolphins.
  • Charlotte likes to paint and cook.
  • She was in a Shakespeare's theatre club.
  • She believed that Gracie's locket was supposed to be hers, but she (indirectly) gave it back to Cleo in the end.
  • Charlotte believed herself to be a "Super Mermaid" because she had all merpeople powers, just like Evie McLaren had, and because this Charlotte was seeing Cleo, Emma and Rikki inferior to her.
  • Charlotte is similar to Rebecca from Zoey 101 in that they both attempt to get between a couple and shortly date the boy then attempt to get revenge on the girl after being dumped.
  • When Charlotte used her powers, she mostly used a open palm.


Main article: Charlotte Watsford/Gallery

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