H2O: Just Add Water

H₂O: Just Add Water, more commonly referred to as H₂O, is an Australian fantasy children and teen drama television show created by Jonathan M. Shiff. It first screened on Australia's Network Ten and as of 2009 ran in syndication in over 120 countries with a worldwide audience of more than 250 million. It was filmed on location at Sea World and other locations on the Gold Coast, Queensland, Australia. The show revolves around three teenage girls facing everyday teen problems while keeping the fact they are mermaids a secret. Each has their own unique, supernatural power related to water.

Only two series with a total of 52 episodes were originally planned, but due to popular demand, a third series was filmed. Series 1 premiered in July 2006, followed by series 2 in September 2007. Series 3 first aired in the United Kingdom in October 2009, with the Australian premiere occurring in May 2010. German Public-service television company ZDF is the co-producer behind the series and distributes it globally around the world.

Rikki Chadwick, Emma Gilbert, and Cleo Sertori, three teenage Australian girls, find themselves stranded on the mysterious Mako Island, where they end up in a pool under a dormant volcano just as a full moon passes above them, bathing the pool in light. The girls are rescued and brought back to shore, only to discover something strange. Ten seconds after coming into contact with water, the girls transform into mermaids. After further experimentation, the girls also discover they have supernatural powers over water. The trio enlist the help of Cleo's friend Lewis McCartney to help them keep their secret and find out more about it.

Everyday situations, such as bathing and dealing with rainy weather, become tricky as the girls struggle with their newfound abilities, which come with many advantages and disadvantages, while also trying to keep them a secret from everyone else, including their families. They soon adapt to their new abilities and lifestyles.

Series two introduces Charlotte Watsford, a rival to Cleo, who dates Lewis after Cleo breaks up with him. She gains mermaid powers and becomes the main antagonist of series two. She has all three of the mermaids' powers. In the end, Charlotte loses both her powers and Lewis, who gets back together with Cleo.

Series three sees the departure of Emma, who has left to travel the world with her family. A new character, Bella Hartley, is introduced and it is discovered that she has been a mermaid since the age of nine. Rikki and Cleo become friends with Bella, but are soon beset by a mysterious tentacle of water with a connection to Mako Island. A new boy, Will Benjamin, also arrives and becomes friends with the trio when he discovers that they are mermaids. The girls learn that Earth is in the path of a comet that could destroy the planet. They try to think of a plan to stop the catastrophe.

All series have been released on DVD in Region 4 PAL format. Series one comprises six individual DVD sets released between September 2007 and November 2008, and a complete series set released in June 2009. Series two comprises three individual sets released between February and September 2009, and a complete series set released in November 2009. Series three comprises two individual sets released in July and September 2012, with a complete series released in December 2012.

A three-disc set, H₂O: Season 1, Volume 1, containing the first 13 episodes of series 1 for Region 1 NTSC format was released on 16 June 2009 by Nickelodeon and Paramount Home Entertainment as a manufacture-on-demand (MOD) DVD-R release via Amazon.com through their CreateSpace service. No follow-up DVD volume releases were made from this initial set, which was later discontinued. A complete series DVD boxed set was released in Region 1 NTSC format on 6 November 2012 from New Video, and all three series were made available for purchase individually beginning on 5 March 2013.