Twelve-year-old Mary was disabled at the age of four by the same virus that took the life of her mother. While she longs to have a horse of her own, she's limited to reading horse books. A talented artist, she spends her days on a blanket in the grass sketching the horses at the farm next door. She falls in love with one of the foals and is outraged to learn the filly is considered worthless as it was born lame.

Mary befriends and enlists the help of twelve-year-old Laura, whose family owns the horse farm. Against the better judgment of the farm manager, a brief reprieve is negotiated for the foal's life. The girls conspire to raise money to save her, but time is running out. Sadly, it appears the expensive surgery the foal needs has little chance to correct her problem anyway. Mary isn't about to give up. She sacrifices what she holds dear, including the trust of her papa, to gain her heart's desire. Will she lose everything in her struggle to save the foal?