s ▁political ▁them es ▁by ▁saying ▁" The ▁par alle ls ▁between ▁imm igration ▁deb ates ▁aren ' t ▁exactly ▁subt le ▁here , ▁but ▁they ' re ▁so ▁well - dra wn ▁it ' s ▁impossible ▁to ▁mind ". ▁Al as da ir ▁Wil kins ▁of ▁The ▁A . V . ▁Club ▁also ▁enjoyed ▁the ▁episode , ▁award ing ▁it ▁a ▁B + ▁grade . ▁He ▁said ▁that ▁the ▁episode ▁" is ▁method ical ▁in ▁how ▁it ▁p aces ▁the ▁setup ▁for ▁next ▁week ' s ▁story ... ▁But ▁no ▁matter , ▁because ▁there ▁are ▁still ▁plenty ▁of ▁some ▁stand out ▁scenes ▁here , ▁in ▁particular ▁H itch ley ' s ▁st ando ff ▁with ▁his ▁mother ▁in ▁front ▁of ▁the ▁church ". ▁He ▁closed ▁his ▁review ▁by ▁saying ▁" the ▁only ▁real ▁questions ▁to ▁answer ▁are ▁does ▁this ▁episode ▁generate ▁anticip ation ▁for ▁next ▁week , ▁and ▁does ▁this ▁episode ▁position ▁“ The ▁Z ygon ▁In version ” ▁to ▁go ▁to ▁places ▁and ▁explore ▁things ▁it ▁couldn ’ t ▁reach ▁if ▁it ▁wer en ’ t ▁the ▁back ▁half ▁of ▁a ▁two - par ter ? ▁I ’ d ▁say ▁yes ▁on ▁both ▁counts ". ▁ ▁Notes ▁ ▁References ▁ ▁External ▁links ▁ ▁Category : Tw elf th ▁Doctor ▁episodes ▁Category : 2 0 1 5 ▁British ▁television ▁episodes ▁Category : Fil ms ▁with ▁screen plays ▁by ▁Peter ▁Har ness ▁Category : UN IT ▁serial s ▁Category : Do ctor ▁Who ▁stories ▁set ▁on ▁Earth ▁Category : T ele vision ▁episodes