In a gritty, tech-noir version of 1930s Manhattan, an ex-cop and his robot partner must stop a killer who's sending the city into chaos.

December, 1933. The city that cannot sleep, where cartels and mobsters go bump in the night. Manhattan's delicate peace is broken when four politicians in the pocket of America's reigning megacorporation are murdered at the Edison Hotel, despatched by an unknown assassin wielding a rare and unique weapon. The NYPD calls upon the only man for the job: Elias Roche, the Nightcaller.

With Upper City bigwigs in a panic and the shadowy Iron Hands poised to make a grab for the Lower City, Roche is having doubts about his role in the complex power structure as a former cop and current mob enforcer. But he sets out to investigate, now under more scrutiny than ever before: a new radio show based on his escapades thrusts unwanted fame upon him, the FBI are breathing down his neck, and a relentless journalist is dogging his every move. Meanwhile, an awakening cynicism in his robot partner, Allen Erzly, is turning their already bleak world upside down. As the pressure mounts, it's a race to find the killer before the eve of the New Year.