Stewart's non-Merlin novels are difficult to classify because they really are not romances, mysteries, or whodunits. Although they have a romantic background, the romance is very understated, especially by more modern standards. They certainly have a strong element of mystery, but it is not as important as other aspects such as the values expounded and the human relationships explored. And the thrust of My Brother Michael is not towards who killed Michael, since the murderer has been known for years. Stewart, when asked about the problem of classification, has said, "I'd rather just say that I write novels, fast-moving novels that entertain." Other categories under which critics have tried to place her works include gothic novels, thrillers, and romantic suspense novels.