David Ralph Martin was an accomplished television and film writer. He contributed numerous scripts for the Doctor Who television series between 1971 and 1979 in collaboration with Bob Baker. Baker and Martin's most notable contributions to the Doctor Who mythos were probably the robot computer K-9 (created for The Invisible Enemy) and the renegade Time Lord Omega (created for The Three Doctors, Doctor Who's tenth anniversary story).Together they were nicknamed "The Bristol Boys" by the Doctor Who production teams with whom they worked. They also worked together on the 1975 children's science fantasy television serial Sky and Into the Labyrinth. In the early 1980s, Martin wrote a series of 4 small illustrated children's stories starring K9. In 1986, he wrote the Doctor Who Make Your Own Adventure book Search for the Doctor.