Hidden Things — Elizabeth Schechter

Margaret Prentice was brought up to believe in science, not magic. Until the chance discovery of an ancient sword leads to a series of magical attacks on her life and the revelation that the sword is part of a greater mystery. A mystery that Margaret is key to solving. A mystery that killed her in a previous life. In order to save herself, Margaret must learn to use powers she didn't know she had from a life she didn't know she lived. But her time is running out -- the immortal enemy who murdered her in the past is preparing to strike again. With everything on the line, can Margaret's journey to self-discovery protect her from reliving a deadly past?