James MacCallum

 voiced several characters for Big Finish Productions, including Isambard Kingdom Brunel.

Doctor Who Main Range

 * Iron Bright - Isambard Kingdom Brunel

The Eighth Doctor Adventures

 * The Great Cyber-War - Nelvin

UNIT: Nemesis

 * The Enemy Beyond - Adam Merchant / Police Officer

The War Master

 * Darkness and Light - Crantz