When the beloved quartet of postal detectives- Oliver (Mabius), Shane (Booth), Rita (Lowe) and Norman (Gustafson)-discover an urgent letter written to God, they delay their own travel plans to help a little girl who's mother's life hangs in the balance on Christmas Eve. With guidance from a mysterious post office volunteer, Jordan (Estes) and Oliver's former Sunday School teacher (Ross), the Postables are surprised to discover they've been a part of more than one miracle on this Christmas Eve.