During the first meeting of the Winter Warmth Book Chat, the lights in Mary’s Mystery Bookshop go out. When the power comes back on, Mary realizes a book has been stolen from the front counter of her shop. But not just any book; This was a signed early edition of "The Murder of Roger Ackroyd" by Agatha Christie! Mary intended to sell the rare and valuable copy and donate the money to help a little girl receive a kidney transplant. Now every person at the event is a suspect in the theft, and Mary has to solve one of her most important mysteries yet. Can she find the stolen book in time to help Isabella?