Detective Ariki Davis arrives in Queenstown where he sticks out as a Cook Island Māori; after a farmer turns up dead at the bottom of One Lane Bridge, tensions quickly escalate between Ariki and D.S.S. Stephen Tremaine.

Stephen's initial suicide theory is upgraded to a homicide investigation as motives and suspects surface; mysterious signs start to haunt Ariki, who struggles to interpret what they mean, both for him and for the case.

Ariki suspects that Stephen's wheelchair-bound wife, Lois, is somehow involved in the case; when Ariki gets an alarming visitation, he goes on a bender; frustrated with the lack of progress, the locals deal out some vigilante justice of their own.

The homicide investigation ramps up; Stephen's wife, Lois, is brought in for official questioning; Ariki's inappropriate behaviour jeopardises both his professional career and the case; stood down from work, he finds himself lost in the wilderness.

Ariki's heroics are rewarded when he's reinstated at work; the Ryders celebrate a hundred years on the farm but the festivities are cut short when the guest of honour goes missing; a confession provides much-needed closure for the town.

A startling revelation at One Lane Bridge puts Ariki in a compromised position; Ariki's gift helps him solve the final piece of the puzzle; the ongoing tension between Ariki and Stephen builds to a deadly climax.