ant ▁as ▁the ▁Doctor , ▁and ▁the ▁last ▁with ▁lead ▁writer ▁and ▁show runner ▁Russell ▁T ▁Dav ies , ▁the ▁spe ci als ▁marked ▁their ▁official ▁departure ▁from ▁the ▁programme , ▁with ▁Matt ▁Smith ▁and ▁Steven ▁M off at ▁replacing ▁them ▁as ▁the ▁Doctor ▁and ▁the ▁lead ▁writer ▁and ▁show runner ▁respectively . ▁ ▁Epis odes ▁ ▁" The ▁End ▁of ▁Time " ▁was ▁the ▁first ▁two - part ▁episode ▁with ▁an ▁overall ▁title ▁and ▁episode ▁numbers ▁since ▁Sur v ival ▁in ▁Season ▁ 2 6 , ▁the ▁final ▁serial ▁broadcast ▁during ▁the ▁series ' ▁original ▁run . ▁ ▁Supp lement al ▁episodes ▁ ▁" Music ▁of ▁the ▁S pher es " ▁was ▁fil med ▁for ▁the ▁ 2 0 0 8 ▁Doctor ▁Who ▁Prom , ▁and ▁the ▁animated ▁six - ep is ode ▁serial ▁Dream land ▁was ▁produced ▁for ▁the ▁BBC ' s ▁Red ▁Button ▁service . ▁ ▁Cast ing ▁ ▁Main ▁characters ▁ ▁These ▁spe ci als ▁marked ▁David ▁T enn ant ' s ▁final ▁run ▁of ▁episodes ▁as ▁the ▁T enth ▁Doctor ▁and ▁Matt ▁Smith ' s ▁first ▁appearance ▁as ▁the ▁newly ▁reg ener ated ▁Ele vent h ▁Doctor . ▁They ▁also ▁featured ▁a ▁string ▁of ▁one - time ▁compan ions ▁beginning ▁in ▁" The ▁Next ▁Doctor " ▁with ▁David ▁Morris sey ▁as ▁Jackson ▁Lake , ▁a ▁man ▁who ▁thinks ▁himself ▁to ▁be ▁the ▁Doctor ▁and ▁his ▁" comp an ion " ▁Ros ita ▁Far isi , ▁played ▁by ▁Vel ile ▁T sh ab al ala . ▁" Plan et