Douglas has been a shelf stacker, bank clerk, tax officer, factory worker, advertising salesperson, taxi driver (for two days), wine waiter (for two hours), journalist and criminal investigator. His early books were all in true crime or criminal history but now he writes fiction, beginning with the Davie McCall series. The final book in the series, OPEN WOUNDS, has been longlisted for the McIlvanney Prize 2016, alongside such authors as Ian Rankin, Val McDermid, Lin Anderson, Doug Johnstone and James Oswald. His next book is THE DEAD DON'T BOOGIE, which will kick off a new series.