Gilbert's first novel, "The Landslide" (1943), a fantasy involving prehistoric creatures uncovered in a landslide in a remote part of Ireland, was dedicated to Reid. The creatures are benevolent, but upset the order of things. It was released to positive reviews, including one from E. M. Forster (a friend of Reid's) speaking on the BBC. A second novel, "Bombardier", appeared the following year. It is based on his volunteer wartime experiences with the 3rd (Ulster) Searchlight Regiment, Royal Artillery in France, including the evacuation at Dunkirk (Gilbert was awarded the Military Medal for blowing up a bridge in the face of an enemy advance). "Bombardier" was a moderate financial success, going through at least two printings.