Third in the intriguing Leonardo da Vinci mystery series known for "capturing the essence of 15th-century Milan". As court engineer to the Duke of Milan, Leonardo da Vinci turns his superior mind to many pursuits- from outlandish contraptions to the odd murder... With war looming ever closer, the iron-fisted Duke of Milan calls upon Master da Vinci to invent the deadliest weapon ever-a flying machine. So da Vinci calls in...