Once again, Woodhouse and Ross (The Medici Guns, The Medici Emerald) dress up the young Leonardo da Vinci as the James Bond of 15th-century Europe, handsome and heterosexual and super-tough: ""Well, Count, if you don't keep a civil tongue in your head, I will ram your safe-conduct between your teeth."" The homicidal Count (who puts a cobra in Leonardo's bed) is just one of the enemies that da Vinci must elude in order to fufill his latest Mission Impossible from Pope Sixtus IV: to free the coastal walled city of Otranto from the infidels who've captured it. He's aided by his loyal ""guns"" and by the luscious Bianca (who disguises herself as a boy), but when Bianca is abducted to the Sultan's harem (where she does very nicely, thank you), Leonardo becomes temporarily distracted. Eventually, however, he pulls himself together and invents the flying machine for an unprecedented gliding attack--with innovative explosives too. Defeated, the Sultan asks: ""Now that you fly through the air, will you teach others to follow you?"" Leonardo says no. ""The lady Bianca compels me to see that my flying machines will be used for killing and for war."" Silly, misleading, but slyly energetic.