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Sphere of Influence was the first story in the audio anthology Susan's War, produced by Big Finish Productions. It was written by Eddie Robson and featured Carole Ann Ford as Susan and William Russell as Ian Chesterton. This was the first appearance of the Sensorites in a Big Finish audio drama.

Publisher's summary[]

Susan’s first mission is one of diplomacy. The Sense-Sphere could prove a valuable ally to Gallifrey.

But she is not the only one who knows the Sensorites of old. Susan will have the support of an old friend.

Ian Chesterton is about to rejoin the adventure he left a lifetime ago!


to be added



  • At the time of his recruitment, Ian Chesterton is talking on the phone with Barbara Wright.
  • Rasmus is a cardinal.
  • The War Council send delegates several centuries back into the Sense Sphere's history, creating a long-lasting diplomatic relationship where none previously existed.
  • Ian uses the clothing machine of a TARDIS.
  • Susan dreams that the Sensorites want cookies made from Arcturan moondust.
  • The Second Sensorite recalls a time in the Sense Sphere's history when a lone group of Daleks discovered the Sphere and attempted to turn it into a new homeworld.



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