In Franklin's well-paced fourth Mistress of the Art of Death novel (after Grave Goods
), Henry II of England assigns his trusted doctor friend, Adelia Aguilar, who studied at the School of Medicine in Salerno, Italy, to accompany his 10-year-old daughter, Joanna, on Joanna's wedding procession to Sicily, where the girl is to marry Henry's cousin, William II. Along the way, the clever and brave Adelia has to not only contend with the dangers facing the princess but thwart a diabolical and conniving assassin named Scarry, who bears Adelia a murderous grudge. The suspense rises as members of the royal party start to die unnatural deaths as they journey across Europe. At times, Franklin, who's obviously done a lot of research into the period, in particular into the House of Plantagenet, overexplains or lapses into pedantic description. Still, both fans of historical fiction and mystery readers will be rewarded. (Apr.)