Yoon-Jung accidentally calls a stranger, instead of her boyfriend, and has phone sex with the unknown man. When Yoon-Jung's relationship with her boyfriend turns sour, Yoon-Jung meets Hyun-Seung, the stranger she had phone sex with.
Four friends bound by destiny and unbeatable in the dark world. When a casino attack goes wrong as a result of betrayal, fate turns them into enemies. Now, forced to aim the gun at each other's hearts, their unavoidable battle begins.
