Doctor Who Fourth Doctor Regenerated 5-Inch Action Figure In his final adventure, the Third Doctor is exposed to a massive dose of deadly radiation while battling the giant spiders of Metebelis III. Later, after getting lost in the Time Vortex, the TARDIS brings him back to UNIT headquarters where, with Sara Jane, another Time Lord named Cho-Je, and the Brigadier watching over him, he regenerates once more. This Doctor Who Fourth Doctor Regenerated 5-Inch Action Figure stands about 5-inches tall and presents the Fourth Doctor as he first appeared, newly regenerated at the end of "Planet of the Spiders."