Lie By Moonlight: Number 4 in series by Amanda Quick
Miss Concordia Glade has never met anyone like Ambrose Wells before. He is bold, clever, and inscrutable - even to the perceptive gaze of a professional teacher such as herself. He is also her only hope to protect the four young girls in her charge from the unscrupulous men who are after them - powerful, shadowy figures who will stop at nothing to get what they want.