After a catastrophic flood engulfs the whole city, Chen Kaiyang, an easy‑going office worker, drowns after being betrayed by his boss and girlfriend. Reborn, he awakens the Doomsday Counterattack System. Every time he gets revenge on his wrongdoers, supplies are rewarded. Standing up to his supervisor grants him powerful gear. Sailing aboard his heavily‑armored ark, the Dawn, he cuts through floodwaters. In the apocalyptic world, he takes down toxic workplace villains, fights zombie kings, accomplishes god‑like deeds as an ordinary human, and finally sails toward a bright future with his beloved.