earance ▁of ▁the ▁K ling on ' s ▁c ran ial ▁rid ges . ▁ ▁The ▁episode ▁sought ▁to ▁answer ▁the ▁question ▁of ▁why ▁K ling ons ▁looked ▁different ▁in ▁Star ▁Tre k : ▁The ▁Original ▁Series ▁than ▁in ▁other ▁series ▁of ▁the ▁franch ise . ▁It ▁also ▁introduced ▁Section ▁ 3 1 , ▁originally ▁seen ▁in ▁Star ▁Tre k : ▁Deep ▁Space ▁N ine , ▁to ▁an ▁earlier ▁time ▁in ▁the ▁Star ▁Tre k ▁canon . ▁ ▁The ▁episode ▁featured ▁a ▁number ▁of ▁guest ▁stars ▁who ▁had ▁previous ▁connections ▁to ▁the ▁franch ise , ▁including ▁James ▁A very ▁who ▁was ▁in ▁the ▁running ▁for ▁the ▁part ▁of ▁W orf ▁in ▁The ▁Next ▁Generation , ▁John ▁Sch uck ▁who ▁played ▁a ▁K ling on ▁Amb assador ▁in ▁two ▁Star ▁Tre k ▁films , ▁and ▁Eric ▁Pier point ▁who ▁had ▁appeared ▁in ▁several ▁other ▁episodes ▁of ▁Star ▁Tre k ▁previously . ▁Some ▁of ▁the ▁standing ▁sets ▁were ▁red ress ed ▁to ▁appear ▁as ▁the ▁interior ▁of ▁the ▁Columbia , ▁and ▁some ▁scenes ▁were ▁fil med ▁outside ▁at ▁the ▁Param ount ▁Studios ▁lot ▁in ▁Los ▁Angeles , ▁California . ▁ ▁Plot ▁Enter prise ▁returns ▁to ▁Earth ▁in ▁time ▁for ▁the ▁launch ▁of ▁the ▁second ▁N X ▁class ▁star ship , ▁Columbia , ▁and ▁Commander ▁T ucker ▁prepar es ▁for ▁his ▁transfer . ▁Meanwhile , ▁En sign ▁S ato ▁and ▁Doctor ▁Ph lo x ▁are ▁attacked ▁in ▁San ▁Francisco , ▁and ▁Ph lo x ▁is ▁kid n apped . ▁Captain ▁Arch er ▁and ▁Lieutenant ▁Re ed