As graduation looms, change comes to Heartland. Amy is offered a full scholarship from an equine program at a university in Colorado. To Mallory's chagrin, Badger comes to work as a hand at the ranch.
Mrs. Bell has an accident in her pony cart and Ty needs to treat Sugarfoot at Heartland. Lou has extended her stay at the ranch and is ducking calls from Peter, who's still in Dubai.
Amy scratches the surface to discover Nick's problems with his horse. Meanwhile, Lou is home for a visit after finding Dubai may not be all that she hoped for.
Amy and Ty are at odds over his purchase of a vintage motorcycle while Caleb goes off to a rodeo in Montana despite Ashley's growing concerns about his life on the circuit.
When a dangerous horse infection called 'strangles' puts Heartland under quarantine, relationships are put to the test and Pegasus becomes very ill.
Victor Whitetail makes a surprise visit to Heartland, which stirs up the past and leaves Tim wondering if Victor was more than just friends with his ex-wife.
While the boys head off on a fishing trip, the girls are left back at Heartland to deal with the havoc caused by a dog, a porcupine and a herd of escaped cows.
Amy leads a rescue search to find Ty and Scott. With Scott near death, Ty must help him survive.
Amy is upset when Ty flies off with Scott to a remote veterinarian call on his last day before heading to school.
Ty protects his mother Lily from his abusive stepfather, who shows up at Heartland to win her back.
Ty and Amy make a trip up to the mountains. But when Ty passes out with a high fever and a blizzard approaches, their remote location is a problem.
After a traumatized Spartan refuses to jump, Amy takes him to a man who fixes horses and hearts. Meanwhile, Ty struggles to tame his new horse, Harley, on his own.
Spartan is stolen and turns up at a horse auction. He is bought by Wes, the man who tried to burn down the Fleming's barn. Amy is determined to get Spartan back.
Kit asks Ty to help her re-home a horse that she was given. Lou resurrects the Hudson Derby as a fund raiser event to help Mrs. Bell and others with some county legal problems.
Hoping that Heartland will have a therapeutic effect on two tough kids on probation, Clint Riley books into the dude ranch for a weekend of teambuilding and discipline.
An oil company begins unwanted exploration on Heartland property, so Lou mobilizes the community against them.
Lisa meddles in Lou's business and personal life with disastrous results. Mackenzie comes back to Heartland to get married, but when a cursed horse also arrives, the wedding is almost called off.
Hollywood starlet Mindy Fanshaw arrives at Heartland under the pretext of honing her non-existent riding skills in anticipation of an upcoming role.
Lou takes three of her former New York co-workers on the Heartland Equine Retreat. Ashley Stanton gets set up with a training partner and horse. Mallory takes Spartan out for a ride.
Lou plans a weekend alone with Scott while the rest of the crew go on a cattle drive. But Lou's plans hit a snafu when the first customers of the dude ranch show up a week early.