After an extended mission of mercy, Mary Martha Hamilton returns home to find her younger sister engaged to the perfect man, Sterling John Cooper. But her sister hardly seems interested in marriage or preparing her new household. Mary always puts her family first and helps her sister, but each time she is around her sister's fiancé, she covets him for herself. In this case dare she steal Sterling? After scraping out a fortune in the mines of California, Sterling is ready to settle down and marry into one of Boston's venerated families. He proposes to one sister, but when Mary shows up, he's afraid he's made a ghastly mistake, but what can he do but honor his word. Then his flighty fiancée leaves him at the altar, but is it too late for him to start over with quiet, gentle Mary, who is a balm to his soul?