Accused of fraud, Ivan Lausman aims to end it all by driving his car into a river. When he's washed up 10km downstream, alive and well, the Aquarians know he's a land-lubber with a residual Aqua gene.

Inspector Jara and Trpelka, the officer assisting her, investigate what happened to Ivan Lausman, but they are unaware that the nixes, or Water People, are also after him and he has gone into hiding.

Jara makes a breakthrough when she receives another set of photos. Lausman attends a nix history lesson by Dr Magda Mrackova and learns about the 'magic water' of Vysehrad lake, hidden beneath Prague.

Eduard is determined to get to the truth about the magic water of Vysehrad and starts a petition to propose the 'coming out' of the nixes. Lausman plans a new venture in the bottled water industry.

The local nix boat dwellers are cynical about Eduard's revolutionary talk. Mr Sikorsky from the Fresh Water Alliance arrives in Prague to 'deal with' Lausman. Jara is removed from the investigation.

Jara has lost interest in the nix case since being hypnotised by Magda. The bottled water scheme is jeopardised. The magic water is revealed to grant a youthful appearance, but there are side-effects.

A tank of algae is poured into the lake that supplies water to Prague, causing a humanitarian catastrophe. Jara is cured of her distraction, and Magda plots to become the next chairman of the council.