18 year old Juri is seriously addicted to online gaming, so much so he becomes isolated from his single mother and pushes his girlfriend to the brink of leaving him. He decides to quit, but is soon lured back by one of his net-mates, Niki, who - when they meet for the first time - turns out to look strikingly like Juri. Niki has a web-address tattooed on his arm and when Juri types it into his computer, he gets drawn into a curious game that grants him the username RAT KING. As the game becomes increasingly dangerous, Niki vows to help Juri get through it. But the game triggers a series of life-threatening events and pretty soon Juri realizes that he is gaming for his life.