My first books were mystery novels, in many ways the simplest novel to write, in terms of structure if not of content. My upcoming novel, The Castle in the Glen, is the story of a famous writer whose dementia means she can’t finish her final novel. This book required not only three time periods but a portion of the famous writer’s novel, written in a style not normally her own. Some caveats in this sort of complex novel: Don’t jump around too often for no reason. Both time periods need to have equal value to complete the story.