Though backed with the thorough research evidenced in Luke's far livelier nonfiction Tudor biographies, this chronicle of Katherine Parr (1512-48), Henry VIII's last Queen, comes across with the cushioned, half-satisfying simplicity of Jean Plaidy's royal profiles. Katherine here is somewhat bland, lacking the quicksilver intelligence or instinct you expect from a female Tudor survivor. In childhood she's the friend and confidant of long-suffering Princess Mary; she weathers the pain-racked reigns of Henry's five queens--whose portraits here are familiar, from bitter Katherine of Aragon to gauche, unfavored Anne of Cleves. Before marrying the King, Katherine is married and widowed twice--with controversy arising from her apparent influence (while still wed to John Neville) in the King's relationship with Thomas Cromwell, the enforcer of Henry's post-schism Church policies. (Luke suggests that one interview with Katherine--in which she tells Henry that the powerful Cromwell is manipulating him--opened the royal eyes and led to Cromwell's fall.) And, after the royal wedlock, Luke investigates Katherine's relationship with the later-martyred religious Reformer Anne Askew (merely a friendly lending of books) and attributes the Queen's release from Henry's frightening detention (for sedition) to a fortuitous howling and wailing. There are convincing glimpses of much-exiled Mary; there's Katherine's post-Henry marriage to handsome, greedy Thomas Seymour. (In the famous bedroom romp between Thomas and young Princess Elizabeth, Luke has Katherine forgive Elizabeth but face down Thomas.) But, despite conscientious attention to all the relevant domestic traumas, Luke's Katherine remains elusive--in a flat, uninspired, sturdily competent historical novel.