His first novel, "Old House of Fear" (1961, 1965), as with so many of his short stories, was written in a self-consciously Gothic vein. Here the plot is concerned with an American assigned by his employer to a bleak locale in rural Scotland—the same country where Kirk had attended graduate school. This was Kirk's most commercially successful and critically acclaimed fictional work, doing much to sustain him financially in subsequent years. "Old House of Fear" was inspired by the novels of John Buchan and Kirk's own Scottish heritage. The story of "Old House of Fear" concerns an young American, Hugh Logan, a World War II veteran who is both brave and sensitive, sent to buy Carnglass, a remote island in the Hebrides. Upon reaching the island, he discovers that the island's owner, Lady MacAskival and her beautiful adopted daughter Mary are being held hostage by foreign spies, who are presumably working for the Soviet Union, out to sabotage a nearby NATO base. The leader of the spies is Dr. Jackman, an evil genius and nihilist intent upon wrecking a world that failed to acknowledge his greatness and whom reviewers noted was a much more vividly drawn character than the hero Logan. Dr. Jackman appears to be a prototype of Kirk's best known character, Mandred Arcane, with the only difference being the former has no values while the latter does.