▁on ▁writing ▁duties ▁along ▁with ▁Super bad ▁co - writer ▁E van ▁Gold berg . ▁Stephen ▁Ch ow ▁had ▁originally ▁signed ▁to ▁play ▁K ato , ▁but ▁then ▁dropped ▁out . ▁Taiwan ese ▁actor ▁Jay ▁Ch ou ▁replaced ▁Ch ow ▁as ▁K ato ▁for ▁the ▁film . ▁In ▁this ▁version , ▁K ato ▁is ▁an ▁or phan ▁who ▁ran ▁away ▁from ▁the ▁or phan age , ▁and ▁was ▁originally ▁employed ▁by ▁Brit t ▁Re id ' s ▁father ▁James ▁as ▁a ▁car ▁mechan ic ▁( also ▁making ▁his ▁coffee ▁with ▁a ▁spe cially - des igned ▁machine ▁he ▁had ▁created ▁for ▁the ▁purpose ), ▁joining ▁Brit t ▁on ▁the ▁steps ▁that ▁lead ▁to ▁him ▁becoming ▁the ▁Green ▁Hor net ▁as ▁Brit t ▁concluded ▁that ▁they ▁had ▁both ▁been ▁was ting ▁their ▁potential . ▁K ato ' s ▁mart ial ▁art ▁skills ▁in ▁this ▁version ▁of ▁the ▁series ▁are ▁so ▁exception al ▁that ▁he ▁claims ▁that ▁time ▁literally ▁slow s ▁down ▁for ▁him ▁when ▁he ▁gets ▁an ▁ad ren al ine ▁r ush ▁in ▁a ▁dangerous ▁situation , ▁as ▁well ▁as ▁his ▁traditional ▁role ▁as ▁mechan ic ▁and ▁driver . ▁Although ▁he ▁and ▁Brit t ▁have ▁a ▁temporary ▁falling - out ▁when ▁they ▁argue ▁over ▁their ▁respective ▁importance ▁to ▁the ▁" Green ▁Hor net " ▁concept - ▁K ato ▁acting ▁as ▁the ▁actual ▁action ▁man ▁of ▁the ▁Hor net ▁while ▁Brit t ▁is ▁the ▁public ▁face ▁as ▁K ato ▁is ▁too ▁fast ▁for ▁any ▁cam eras ▁to ▁see ▁him - ▁they ▁patch ▁up ▁their