Five years ago, a catastrophic disaster ended humanity’s peaceful life in a single day. Mysterious “Special Zones” of varying difficulties began appearing across the globe.

Maya Ichijo, who nearly cleared all 100 zones to achieve the “Grand Slam,” is betrayed by his comrades and killed during the final trial.

But in his last breath… he awakens in the world before the disaster struck.

Now, armed with his past memories, he vows revenge— Because in this world, the real monsters aren’t the zombies… but humans.