Dr. Linda Denman is a marine biologist that arrives in the town, in order to study fishes. She is the primary villain/antagonist of Season 1.


Lewis applies for a job with Dr. Linda Denman so he can use her high grade technology to study a D.N.A sample of Cleo. Lewis had a crush on her much to the dismay of Cleo who takes an instant dislike in her. Dr. Denman finds the sample when Lewis carelessly leaves it in the lab, when he goes home for the day. Dr. Denman adds water to it, then observes the cellular mutation of the sample. Dr. Denman persistently inquires Lewis about the sample. She writes a paper called "H2O: Just Add Water" which is presumably where the series gets its name. Lewis sees the article on her computer and erases it.


Dr. Denman leaves town on a six month trip then reappears in an attempt to find the source of the mysterious sample. Dr. Denman finds out the girls secret and traps them in the Moon Pool, planning to do some tests on them, Harrison Bennett helps her but wants no harm to come to the girls. Zane frees them, with the help of Lewis, but then Cleo, Rikki and Emma come back to the Mako Island to give up their powers during the Lunar Eclipse Dr. Denman begs the girls not to give it up but they refuse to listen. The girls only lose their powers temporarily for twelve hours, but Dr. Denman believed it to be forever and gives up.

Behind the Scenes

She was portrayed by actress Lara Cox.


Main article: Linda Denman/Gallery

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