Mark Elstob

 was an actor who appeared in several Big Finish Productions. He started his career mainly in the theatre with occasional appearances in film and television, one of these being a stint in the soap opera Emmerdale.

More recently, Elstob has become the new voice of Number Six in Big Finish's audio revival of.

The War Doctor

 * Pretty Lies - Editor/Old Man

Tenth Doctor Adventures

 * The Sword of the Chevalier - Joxer/Butler

Torchwood

 * ''The Dying Room - Herr Grau

The War Master

 * ''Beneath the Viscoid - Glortz

The Churchill Years

 * I Was Churchill's Double - Kaiser Wilhelm III / John Logie Baird