Amy deals with a major upheaval in her life, Lou copes with the reality of being the mayor of Hudson, and Georgie revisits her dream of the Olympics. TV-PG

Amy must face a difficult truth when her efforts to help a young girl form a connection with her new horse takes an unexpected turn, and Lou faces harsh criticism as mayor. TV-PG

Amy grudgingly helps Ty's mother, Lily, with a traumatized racehorse. Lou gets into even more hot water when she tries to sell Hudson as a must-see tourist destination. TV-PG

Disaster strikes when a train derails and causes an explosion that threatens the town. A wild fire quickly spreads toward the rodeo grounds, and Amy rushes to save the abandoned horses there. TV-PG

The wild, black stallion that Amy rehomed from Will's ranch is brutally forced out of the herd by the new leader; leaving Amy to track down the injured horse and nurse him back to health. TV-PG

A group of wild horses need new homes; Amy must get back to her Miracle Girl roots and host her first horse clinic in over a year. TV-PG

Tim seeks unlikely help when he finds himself competing in a polo match; Amy is concerned her daughter isn't adjusting well to her new reality and makes a decision that worries Jack. TV-PG

Caleb finds a memento from the past that he thinks will have special meaning for Amy; surprisingly, it's Jack who has some mixed emotions stirred up by the gift. TV-PG

Quinn's wealthy father arrives at Heartland with a life-changing proposition for both Amy and his son. TV-PG

Amy works with a challenging horse to help a friend of Clint's; she also revives a dream to rebuild the jumping course that she and Spartan practiced on so many years ago. TV-PG