
Sully arrives in Boston and discovers that he's facing worthy competition for Mike's affection in the form of Dr. William Burke. Sully at first settles uncomfortably into Mike's Boston surroundings, but later, with prodding from the kids, submits to a grand makeover. Later, Sully romances Mike with dining and dancing, even attending an opera together. At an all-male medical society, Dr. Burke steps aside so that Mike can present a paper on Indian medicine, while Sully looks on. Afterward, Sully overhears Dr. Burke proposing marriage to Mike and heads back to Colorado, but not before confessing his love to Mike. In the end, Mike declines Dr. Burke's marriage proposal and Mike and the kids return to Colorado, where Dr. Mike returns Sully's declaration of love with a vow in kind.
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.