
Mike receives an emergency telegram from her sister Rebecca -- her mother is gravely ill. Mike rushes to Boston to her mother's side, the Cooper kids in tow, where Dr. Mike and her ""roughhewn"" children are met with raised eyebrows by Dr. Quinn's own family. While consulting with Elizabeth Quinn's attending physician, Dr. Mike meets a handsome and progressive Doctor, Dr. William Burke. Dr. Mike's prognosis of her mother (hepatitis) differs with Mrs. Quinn's doctor, Dr. Hanson, who diagnoses cancer. Dr. Burke, however, believes Dr. Mike may be onto something. They have a lot in common and develop a strong mutual admiration for each other. They work together to cure Mrs. Quinn and some of Dr. Burke's other patients. Meanwhile, Matthew chafes at being stuck in Boston away from Ingrid, while Colleen appreciates the learned and cultured atmosphere and Brian adores the candy stores. Just when everyone has settled comfortably into the Boston routine, Sully shows up, unannounced and in buckskin
After Snowbird gives Mike an Indian pony, Flash, in thanks for her work at the reservation Mike tries to enter the Territory Stakes Race, but race officials, Loren and Jake, won't allow a woman to ride. Dr. Cassidy arrives from Denver with his champion horse and spurns Mike attempts to speak to him colleague to colleague. Dr. Cassidy's rider, Drew, is injured and Mike diagnoses cranial compression, yet Dr. Cassidy refuses Mike's assistance. Drew dies and an angry Mike is determined to enter the race, disguised as a man. Meanwhile, with encouragement from Grace, Brian enters a pie-baking contest and is met with skepticism from Colleen and Loren. To everyone's surprise, Brian is declared the winner. Mike rides the race of her life and wins, but is disqualified when her disguise is revealed and Hank, riding Dr. Cassidy's horse, is declared the winner.