While Connolly threatens to transfer the Tsalal case to Anchorage, Navarro and Danvers make a discovery that brings the former colleagues closer together.
When night falls in Ennis, Alaska, the eight men who operate the Tsalal Arctic Research Station vanish without a trace. To solve the case, detectives Liz Danvers and Evangeline Navarro will have to confront the darkness they carry in themselves.