Bruce Murdoch and his chief Sir Robert Holt, are involved in the Secret Service.  The books portray thrills and spills, and adventure pertinent to the time in which they were written, but also relevant and representative of many secret battles fought since.

The Bruce Murdoch series were written under the pseudonym Norman Deane between 1939–1942.

• Secret Errand (1939)
• Dangerous Journey (1939)
• Unknown Mission (1940)
• The Withered Man (1940)
• I Am the Withered Man (1941)
• Where is the Withered Man (1942)