▁own ▁moral ▁code ". ▁He ▁li ken ed ▁the ▁Doctor ' s ▁debate ▁to ▁that ▁of ▁the ▁Four th ▁Doctor ▁( Tom ▁Baker ) ▁in ▁Gen esis ▁of ▁the ▁D ale ks ▁( 1 9 7 5 ) ▁and ▁the ▁Fif th ▁Doctor ▁( Peter ▁Dav ison ) ▁in ▁Res urre ction ▁of ▁the ▁D ale ks ▁( 1 9 8 4 ). ▁In ▁addition , ▁review ers ▁noted ▁that ▁the ▁episode ▁presented ▁its ▁characters ▁with ▁" sh ades ▁of ▁grey ", ▁rather ▁than ▁black - and - white ▁villa ins ▁typically ▁seen ▁in ▁the ▁show . ▁ ▁Broadcast ▁and ▁reception ▁ ▁" A ▁Town ▁Cal led ▁Mer cy " ▁was ▁first ▁broadcast ▁in ▁the ▁United ▁Kingdom ▁on ▁BBC ▁One ▁and ▁BBC ▁One ▁HD ▁on ▁ 1 5 ▁September ▁ 2 0 1 2 ▁and ▁on ▁the ▁same ▁date ▁on ▁BBC ▁America ▁in ▁the ▁United ▁States . ▁O vern ight ▁ratings ▁showed ▁that ▁it ▁was ▁watched ▁by ▁ 6 . 6 ▁million ▁view ers ▁live , ▁the ▁highest ▁over night ▁figure ▁of ▁the ▁sevent h ▁series ▁thus ▁far . ▁It ▁was ▁the ▁third ▁most - watch ed ▁programme ▁of ▁the ▁day , ▁and ▁was ▁also ▁the ▁most ▁popular ▁programme ▁the ▁next ▁day ▁on ▁BBC ▁i Player . ▁It ▁later ▁came ▁in ▁third ▁on ▁the ▁i Player ▁chart ▁for ▁September ▁with ▁ 1 . 4 ▁million ▁requests , ▁behind ▁the ▁first ▁two ▁episodes ▁of ▁the ▁series . ▁When ▁final ▁cons olid ated ▁view ers ▁were ▁taking ▁into ▁account ▁the ▁figure ▁rose ▁to ▁ 8