[1] He joined the Labour League of Youth and later the Hull Branch of the Socialist Party of Great Britain, but was expelled from the latter in 1933 for his involvement in an internal dispute.
His career in teaching was interrupted by the outbreak of World War II; Billany joined the army in 1940 and became an officer as lieutenant in the 4th battalion of the East Yorkshire Regiment.
The Opera House Murders, a thriller, and The Magic Door, a book for boys, were published in 1940 and 1943, respectively.
After the capitulation of Italy in September 1943, Billany fled to the countryside with his manuscripts, working on them for weeks while hiding from the German army.
These manuscripts, The Cage and The Trap, were received by Billany's family in 1946 and eventually published to wide acclaim.