The Sorcerer's Letterbox — Simon Rose

In a hidden drawer, located in the base of an old wooden box, Jack discovers a letter from a boy calling himself Edward. Penning a reply, Jack is astonished to be corresponding through time with Edward V, one of the famous Princes in the Tower. Traveling back in time, Jack attempts to rescue Edward and his brother from death, and is soon fighting for his life in the terrifying London of 1483.