Robert Sloman was born in Oldham, Lancashire, England, in 1926. He attended St. Boniface School and Exeter University. After a brief stint in repertory theatre, he took a job with the Sunday Times circulation department, eventually becoming distribution manager.
Sloman never lost his love for the theatre, co-writing two successful plays with Laurence Dobie, "The Golden Rivet" and "The Tinker." "Tinker" was later made into a film, The Wild and the Willing, in 1962. In 1972 he was approached by friend Barry Letts about writing a story for Doctor Who. They collaborated under the mutual pseudonym of "Guy Leopold," with the result being "The Daemons," still considered by many to be among the best stories in the history of the original series. Under his own name, Sloman also wrote the stories "The Time Monster," "The Green Death," and "Planet of the Spiders," the last marking Jon Pertwee's final regular appearance as the Doctor.
Sloman retired from the Sunday Times in 1974, moving to Burgess Hill, Sussex, becoming a wholesale distributor for all Sunday papers. He also developed a passion for sailing, and acquired a second home in Spain. He died in 2005.