The Destroyers ( audio story ) The Destroyers was a full cast audio drama produced by Big Finish for " The Second Doctor Box Set " , a part of " The Lost Stories " series , released in December 2010 . It was based on an unproduced script for a pilot episode written by Terry Nation in 1966 . This was planned as a spin - off series for television and featuring the Dalek s , the Space Security Service and the character Sara Kingdom , all of whom Nation had featured in " The Daleks ' Master Plan " . The actual title of the proposed spin - off series is not known . A synopsis of the script ( see : " The Destroyers " ) was published in " The Official Doctor Who & the Daleks Book " in 1988 . Terry Nation ' s original story was adapted for Big Finish by Nicholas Briggs and John Dorney . It largely switched the roles of Sara and David . It starred Jean Marsh as Sara Kingdom , Alan Cox as Mark Seven , Chris Porter as Jason Corey , Alex Mallinson as David Kingdom and Nicholas Briggs as the voice of the Daleks . Publisher ' s summary . When the crew of Explorer Base One is attacked by the Dalek s , Space Security Agents Sara Kingdom , Mark Seven and Jason Corey investigate . They discover a plan that threatens the future of the entire galaxy . . . Plot . Carson , a member of the Space Exploration Team who have spent two days on the surface of the giant meteorite M5 , patrols inside a force field surrounding their temporary home — Explorer Base One . Their original rocket survey showed no signs of any advanced life on the meteorite . However , the Daleks have a secret underground base and they penetrate the force field and massacre Carson , his superior Tom Wayne ( who wears two short arrows on his uniform ) , Morgan and almost the entire crew . They take two crew , an injured space engineer ( named Philip Leigh in the original script ) and David Kingdom away for interrogation . Meanwhile , Special Space Security Forces ( SSS ) agents Jason Corey , David ' s sister Sara Kingdom and android Mark Seven are exploring M5 , having arrived with the team . Noticing the glow of the blazing base , they hurry back . They discover a crew member named Whitman , dying . He tells them that the Daleks attacked and took a few prisoners . Mark Seven recalls that the Daleks are only recorded as having penetrated their galaxy on two occasions : seventy years earlier , when they slaughtered the garrison on Alpha - Millenia ; and six months after that , when a Dalek ship was identified near Mars . There had been no reports since then . The native carnivorous carrion plants begin to feast on the dead bodies strewn around . In the Daleks ' headquarters , their instruments detect movement at the base . They send a patrol out to annihilate whatever is alive there . When David asks for help for his injured colleague , the Daleks simply kill him , as they still have one healthy prisoner in David . The SSS agents follow the Dalek tracks towards their tunnel system , when the Dalek patrol approaches them . Jason , Mark and Sara hide in the bushes , where they are attacked the carnivorous plants . Continuing to the caves , Jason and Mark venture further in while Sara guards the entrance . She is attacked by some sort of shadowy spectre which envelopes her in webbing . She is only released when the creature is scared off by the returning Dalek patrol . She follows Jason and Mark to alert them . Inside , their way forward is blocked by a chasm , but knowing there must be some way for the Daleks to cross it they hide , and see the two Daleks activate a retractable bridge . As one crosses they jump the other , tossing it into the chasm . The first Dalek tries to return but Sara deactivates the bridge , sending the creature plunging into the abyss . In the headquarters , the commanding Black Dalek relays orders to his Silver Dalek subordinate to inform the Supreme Dalek on Skaro that their mission is complete . They tell David that the elimination of the M5 base is part of their strategy for the destruction of Earth and its colony planets . The Black Dalek orders their ship prepared for departure . The SSS agents arrive at the outer doors in time to see David , but not in time to stop him being taken away as the Dalek ship launches . David Kingdom ' s fate is unknown . Mark Seven wrote a file about the incident , which Mavic Chen consulted when Bret Vyon and he met Sara Kingdom " so many years " later in 3999 . ( AUDIO : " The Guardian of the Solar System " ) References . " to be added "