The past year has brought unexpected change to the Heartland family. While 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.

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. Meanwhile, Lou faces harsh criticism as mayor, and a cattle drive brings up difficult memories for Jack.

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.

Disaster strikes Hudson 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.

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.

Tim seeks out help from an unlikely person when he finds himself competing in a polo match; Amy is concerned her daughter isn't adjusting well to her new reality; she makes a decision that worries Jack.

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

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

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.