"Tatau" follows Kyle (Joe Layton) and Budgie (Theo Barklem-Biggs), two twenty-something friends from London that set off to travel the world. Ahead of the journey, Kyle gets a Maori-style tattoo to celebrate their eventual destination: the Cook Islands.

When snorkeling in a lagoon, Kyle finds the dead body of a local girl, Aumea, tied up underwater. Returning to the lagoon with the police, Kyle finds her corpse has disappeared. But Kyle knows what he saw. Desperate to uncover what happened, Kyle and Budgie find themselves sucked deeper and deeper into a world of Maori myths, symbols, and hallucinatory visions... until finally the full meaning of Kyle's tattoo is revealed.