After the Great Zapfish, Inkopolis' primary power supply, is stolen, Cap'n Cuttlefish employs a Splatoon of Inklings to travel to the Octarians' secret underground base and retrieve it. Players assume the role of Agent 3 of the New Squidbeak Splatoon and traverse the treacherous landscape of Octo Valley in order to reclaim various lost Zapfish, Sunken Scrolls, and Power Eggs.