Denver, 1885. Two redheaded Irish sisters find themselves in a desperate struggle, one that could mean life or death for a newborn infant. Elise Gallagher, a laundress with a heart of gold, is determined to protect the child. Her sister, Maeve Gallagher, a midwife with less scrupulous intentions, plans to sell the baby, although she knows the mother will soon marry and want it back.

To save the baby, Elise steals it away. Enraged, Maeve accuses her sister of kidnapping and sends the law after her. Elise is arrested by U.S. Marshal Garrick Longworth on a train bound for Denver. However, in a moment of chaos, she and the baby are kidnapped by train robbers.

Can Marshal Longworth capture the gang and rescue Elise and the child? With danger lurking at every turn and Elise's outlaw brother hot on their trail, their journey home becomes increasingly perilous. Will the marshal turn Elise in despite his growing feelings for her? And will Elise be able to thwart Maeve's attempts to see her jailed once they return? Amidst the turmoil, will Elise confess her love for Garrick and find the happiness she truly deserves?