H2O: Just Add Water (2006–2010)

And Then There Were Four 

Charlotte's stubborn nature and thirst for knowledge leads her to Max, who confirms her suspicions and leads her to the Moon Pool. Lewis meanwhile is having trouble trying to keep their relationship together.


Colin Budds


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Episode credited cast:
Brittany Byrnes ... Charlotte
Cariba Heine ... Rikki
Claire Holt ... Emma
Phoebe Tonkin ... Cleo
Angus McLaren ... Lewis
Cleo Massey ... Kim
Craig Marriott ... Frank
Ashleigh Brewer ... Gracie (archive footage)
Alan David Lee ... Don Sertori
Martin Vaughan ... Max Hamilton
Rest of cast listed alphabetically:
Matthew Scully ... Young Max (archive footage)


Lewis takes everything back to Max Hamilton, not realizing that he is being followed by Charlotte. When Max discovers that Charlotte is Gracie's granddaughter, he tells her everything he knows. Charlotte goes back to the moon pool during another full moon and this time goes into the water while the moon passes overhead. Written by Anonymous

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Plot Keywords:

teenager | mermaid | See All (2) »


Drama | Family | Fantasy



Did You Know?


[All trivia items for this title are spoilers.] See more »


Don Sertori: Cleo, it's a school night, remember?
Cleo: Yeah, I know. But, Dad, it's really important.
Don Sertori: Really. Tell me, what's so important about tonight?
Cleo: Well...
[glancing uncomfortably at Emma and Rikki]
Cleo: It's a full moon.
[whispering to her friends:]
Cleo: Just go with me on this.
Don Sertori: A full moon?
Cleo: Yeah. We're doing a special project on the moon, and we need to be together. Tonight. Right, guys?
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No Ordinary Girl
(main title theme)
Performed by Kate Alexa
Written by Shelley Rosenberg
(Season 2)
See more »

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Release Date:

15 February 2008 (Australia) See more »

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