Aftershock follows four groups of people in the minutes, hours and days after Wellington is struck by a magnitude 8.2 earthquake and subsequent tsunami. Buried office workers must pull together. Strangers, caught by the tsunami on a ruined motorway, put themselves in danger to save others. A mother must reunite her family. And, at the centre of the rescue operation, a controller is bunkered down at Wellington’s Emergency Management Office.

Dans les îles anglo-normandes, à la vieille du débarquement, deux commandos de Kiwi sont envoyés pur détruire des emplacements d'armes à feu allemandes. Ils découvrent alors qu'un Nazi tente de libérer des forces démoniaques sur terre, dans le but de gagner la guerre.