In an instant, Ryouta Sakamoto is whisked away from his Btoom! gaming session to an enigmatic island. He's given a day's worth of food, a sack of bombs, a peculiar crystal lodged in his hand, and a memory loss. However, he soon comes to the realization that the game he loved is now his life. His first encounter with another player taking a shot at him confirms it. Someone has brought Btoom! into reality, enslaving many into the game, creating a ferocious army of players armed with a variety of explosive weapons known as BIM. Ryouta is fortunate that he's a skilled Btoom! gamer. But, in this deadly reality, there is no safe mode or extra lives, and escape is only possible if he murders seven others before they eliminate him. Will his game-based abilities suffice to keep him breathing?