AfterfiveyearsofwarinSyria,Aleppo'sremainingresidentspreparethemselvesforasiege.Khalid,SubhiandMahmoud,foundingmembersofTheWhiteHelmets,haveremainedinthecitytohelptheirfellowcitizens-andexperiencedailylife,death,struggleandtriumphinacityunderfire.