From girlhood through middle age, Rachel and Miri -- two Jewish women living in Colorado -- struggle to sustain a complex, often competitive friendship throughout the challenges that arise over many decades. Miri's young daughter, Tamar, initially appears to offer the long-time friends a link that will strengthen their uneasy bond. But when Tamar develops a passion for a dangerous sport even before the girl reaches puberty, Rachel and Miri's friendship faces a test more severe than any the women have ever experienced.