Gary Martin Dobbs (Known by the pen name Jack Martin (Born in 1965) is a British writer and actor, known for a string of Western novels for Robert Hale's Black Horse Western imprint, including Arkansas Smith, The Ballad of Delta Rose, and The Afterlife of Slim McCord. In 2016 a digital edition of Tarnished Star was issued by Piccadilly Publishing under the alternative title of LawMaster. The title change refers to the title used for the script by Neil Jones and Gary Dobbs which is optioned for a feature film.

Dobbs is the writer of the series of mysteries featuring the character of Granny Smith. As an actor Dobbs has appeared (often unaccredited) in many British TV shows, as well as in the films The Reverend and Risen. In 2014 Dobbs wrote the 2013 non-fiction historical book, Cardiff and the Valleys in the Great War, published by Pen and Sword Books. Other non fiction works include Dark Valleys (2016) ,Cardiff at War 1939 - 1945 (2018) and A Date with the Hangman: A history of capital punishment.