The Secret of the Hidden Scrolls: Journey to Jericho, M. J. Thomas, Worthykids/Ideals, 2018.
Peter and Mary return in the fourth book in the Secret of the Hidden Scrolls series. In this adventure, the children learn that Great Uncle Solomon used to be a spy during the war. Their uncle teaches them a few things about being a spy.
Mary and Peter’s adventure takes them to the days of Joshua, just before he leads the Hebrew people to march around Jericho. Like in the other books, the children have to solve the secret of the hidden scroll to return home.