Falconer joined the British Royal Marines at the age of 17. At 19 years of age, he attended SBS selection in Poole Dorset and was one of nine Marines to successfully complete the course out of 150 men. Exceptionally he had been allowed to undergo selection without being required to build experience in a Commando formation although later in his career he was posted in the Commando role as a broadening opportunity.

Falconer served the majority of his career with the SBS. He also underwent selection to 14 Intelligence Company and served in that role in Northern Ireland. He served in the US, Mediterranean, and Northern Ireland.

Since leaving the SBS, Falconer followed the route of many ex-special forces members and moved in the world of Private military companies. There he has worked as a hostile environment instructor and security consultancy for journalists and has operated in many countries including those in Africa, the Middle East and Asia. .

His first literary publication was First into Action which was a non-fiction account of the actions carried out by the SBS and was initially seen as an attempt to go against the tide of many of the British Special Forces biographies of the time. The tales were to a lesser extent on the heroic actions of the men and show the more humorous, realistic side of the troops. The book did, however, highlight the rivalry and antagonsm between the Special Boat Service and Special Air Service and the history behind their conflict.

Such was the success of the book, Time Warner publishing again approached Falconer with the view to him writing a military based novel. He has since written a series of novels, all except one based around his central character John Stratton. Stratton is a former SBS operative and appeared in The Hostage, The Hijack, The Operative and his first Hardback book Undersea Prison, while the central character in The Protector is former Royal Marine turned private security contractor Bernie Mallory.

Duncan Falconer divides his time between England, North America and South Africa.

Non-Fiction

• First into Action: Dramatic Personal Account of Life Inside the SBS

Fiction

• The Hostage
• The Hijack
• The Operative
• The Protector
• Undersea Prison
• The Mercenary (published: 4 Jun 2009)
• Traitor