In the tumultuous era of the Italian Renaissance, a young man named Andrea Orsini finds himself caught in a web of intrigue and danger. Driven by a thirst for revenge against the powerful Orsini family, he assumes the guise of the legendary "Lion of Florence," a masked vigilante who strikes fear into the hearts of the corrupt. As Andrea's actions become bolder, he attracts the attention of both the authorities and the enigmatic Lucrezia Borgia, a woman of extraordinary beauty and cunning. With each daring exploit, Andrea's true identity hangs in the balance, and he must navigate a treacherous path where trust is scarce and betrayal lurks around every corner.

Justin Caryll was an unwilling hero: an unwilling plotter of revenge, an unwilling spy and an unwilling pursuer of the woman he loves. Justin must thread a perilous path through various sticky wickets, between the machinations of his foster father, the violence of his brother, the relentless pursuit by the government's agent, his hopeless love for the hapless heroine, and the struggles of his own conscience. Fortunately, Justin is equipped with the skill and speed to lunge and parry, both verbally and with a sword, to make his way through 18th century London with plenty of aplomb, in the midst of Jacobite plots and financial finagling by the ultra rich.