Zhangamiddleagedmanstrugglingwithadeadendjobasaninsurancesalesperson,onthevergeofdivorcewithhiswife,losingcustodyofherdaughterandontopofallthishehadtotakecareofhisfatherwho'ssufferingAlzheimer's.UnknowinglyZhangwasinvitedtojoinanundergroundfightinggameforfinancialpurposesbuteventuallyZhangbecomeshookedonthefightsandturnsprofessional.