Mary Newbury is forced to leave her home in England after her grandmother, a healer, is tried and hanged for practicing witchcraft.

With the help of a woman who turns out to be her mother, Mary boards a ship to America with a group of Puritans also bound for the New World. Mary soon realizes that she is in just as much danger in her new home.

She keeps a secret diary that begins, "I am Mary. I am a witch." Mary's fascinating story unfolds in her own words.

Excellent. I just ordered the sequel!