If there's been a theme in Justine Meade's life, it's loss. Her mother, her home, even her son. The one bright spot in her loss-filled life, the partner she could always count on, was Mack, her grey and black Sheltie - that is, until she is summoned back to her childhood home after more than twenty years away. Ed and Alice Parmalee are mourning a loss of their own. Seven years after their daughter was taken from them, they're living separate lives together. Dancing around each other, and their unspeakable heartbreak, unable to bridge the chasm left between them. When they find a little black and gray dog by the side of the road, they take him in. Fiercely loyal, acutely perceptive and guided by a herd dog's instinct, Mack has a way of bringing out the best in his humans. Whether it's as Justine's partner, or just the ebb and flow of a family's rhythms, it's as though the little Shetland Sheepdog was born to bring people together. Everyone needs Mack. But to whom does the little dog who danced belong?