Players in Atomfall awaken with amnesia in a post-apocalyptic landscape five years after the Windscale Fire, which has turned Cumberland into a quarantine zone controlled by the British government. The game features distinctive gameplay mechanics that emphasize survival action, where enemies do not have levels or health bars, and a well-placed headshot results in an instant kill. Players engage with a unique investigation system through an Investigation Journal that fills with 'Leads' as they explore, converse, and read documents. Interactions with NPCs allow for various resolutions without a morality system. Visually, the game presents mixed quality, with beautiful environments but rudimentary character models. Atomfall is optimized for smooth performance across platforms, maintaining a consistent 60fps on consoles.