​Margret MacBride loves her children more than life itself, but as a young widow, she can't support herself and her children on a maid's salary. After losing their home they struggle for years to survive living on the streets. Distraught, Margret turns to the church for guidance.
 
Mary Agnus convinces Margret her children will be better off if she turns them over to the Catholic Foundling Aid Society for placement in a home. Little did she know her children would end up on the Orphan Train heading into the western territories.

Taken from the only home they have ever known, Elizabeth and Conner MacBride are frightened and homesick. Their aid worker, Mrs. Kelly, does her best to comfort the children and help them come to terms with their new situation.

When Elizabeth finds herself in trouble after a run-in with the foundlings' home's director, Sister Mary Clare, and bullied by one of the other children, Mrs. Kelly puts her job on the line to get Elizabeth and her brother on the Orphan Train and find them a new home in the wild west.