In this dark prison, 50 people are imprisoned. They come from different places, including military men, boxers, martial arts masters and street gangsters. What they have in common is: 1. Good at fighting; 2. There is no hope of escape; 3. They're all women! Yes, in this one-on-one underground female competition, they have to fight with their lives, no matter how good they are, they are the bets of the rich. And only by taking the lives of the other 49 people, can the last profiteer be free from the sin of suicide among the people.