The Captive Within opens the day after Joy on This Mountain ends. The two infamous houses of Corinth, Colorado, are closed and the young women who had been imprisoned there have been released. Soon after, Rose and Joy leave Corinth to establish a home and a haven for "their" girls in Denver.

Before long, Rose and Joy face a heartrending challenge: What does it take to unlock and free the soul of a defiled woman? And as they wrestle for a foothold in Denver, Rose discovers that the long-abandoned house given to them hides a dark secret of its own.