One With the Darkness — Susan Squires

Contessa Donnatella di Poliziano has power, beauty, and--as a vampire--eternal life. Her overwhelming regret is a mistake she made centuries ago when she chose not to transform her one true love, Jergan, into a vampire too. Donnatella's choice has deprived her of the only true love she's ever known. But just as all seems lost, the discovery of a 300-year-old note leads her to a gift left by her old friend, Leonardo da Vinci: a machine to take her back in time to rewrite the history of her heart...

Once back in time, Donnatella's memory of the intervening years is lost. Yet when she sees the breathtaking Jergan from afar, she feels like she has always known him. The instant attraction she feels draws them together. For Donnatella, the romance is tantalizing, awakening a passion that feels both old and new. But as the two fall in love again, a new danger threatens to tear them apart. Now Jergan's love for Donnatella will be tested in a most perilous way--and if he fails, the two lovers will be separated again...for eternity.