▁along ▁with ▁" Once ▁Upon ▁a ▁Time ▁in ▁Spring field " ▁and ▁The ▁Sim ps ons ▁ 2 0 th ▁An ni versary ▁Special ▁– ▁In ▁ 3 - D ! ▁On ▁Ice !. ▁ ▁Cultural ▁references ▁The ▁plot ▁of ▁" The ▁Bob ▁Next ▁Do or " ▁is ▁based ▁on ▁the ▁movie ▁Face / Off . ▁The ▁opening ▁c ouch ▁g ag ▁also ▁features ▁Harold ▁from ▁ ▁the ▁ 1 9 5 5 ▁children ' s ▁book ▁Harold ▁and ▁the ▁Pur ple ▁C ray on . ▁Bart ▁tries ▁to ▁tempt ▁W alt ▁to ▁sing ▁" Three ▁Little ▁Ma ids ▁from ▁School ▁Are ▁We " ▁from ▁The ▁Mik ado ; ▁the ▁same ▁song ▁was ▁also ▁used ▁in ▁an ▁earlier ▁episode , ▁" C ape ▁Fe are ", ▁which ▁also ▁featured ▁S ides how ▁Bob . ▁Later ▁in ▁the ▁show , ▁when ▁S ides how ▁Bob ▁reve als ▁his ▁true ▁identity , ▁he ▁exc laim s ▁he ▁is ▁now ▁" able ▁to ▁sing ▁all ▁the ▁Gilbert ▁& ▁S ull ivan ▁I ▁dam n ▁well ▁please ", ▁followed ▁by ▁him ▁pulling ▁a ▁Japanese ▁fan ▁out ▁of ▁the ▁glo ve ▁box ▁and ▁singing ▁the ▁opening ▁notes ▁of ▁" Be hold ▁The ▁Lord ▁High ▁Exec ution er ", ▁another ▁number ▁from ▁The ▁Mik ado , ▁to ▁Bart ' s ▁horror . ▁Mar ge ▁and ▁H omer ▁tell ▁Bart ▁that ▁a ▁lot ▁of ▁people ▁have ▁voices ▁like ▁S ides how ▁Bob ' s , ▁such ▁as ▁" F ras ier ▁on ▁Cheers , ▁F ras ier ▁on ▁F ras