After studying art in Gloucester, Frank Humphris worked as a painter and illustrator for a while. During World War II, he was a cartographer at the War Office. In 1952 Humphris took over the graphic duties of the 'Riders of the Range' series from Jack Daniel and Angus Scott. This western series was a comic adaptation of a radio play from the late 1940s and appeared in Eagle magazine. Humphris drew the series until 1962.
Afterwards, he started 'The Devil's Henchmen', also in Eagle, and he made illustrations for several other magazines. After creating 'Gun Lore' in Boy's World, he returned at to Eagle, where he took over the 'Blackbow the Cheyenne' series from Victor de la Fuente. From the 1970s, Frank Humphris has devoted his time to writing and painting.