Tae-seong, a mixed martial art professional with excellent skills, is injured and got disqualified as he gets caught up in a fight ahead of his UFC debut. Hye-na, Byeong-jin's younger sister and video streamer, encourages Tae-seong to make a comeback. Hye-na finds out that the man who injured his brother is Ho-yeol, the champion of "Blood Street", an illegal gambling game site where one can bet after a real street fighting match.