Lou is in Dubai. Caleb & Ashley are on the circuit, and Amy has just returned from the Ring of Fire tour and Jack is glad that folks are coming home as the ranch is too much for him by himself. Then, Amy is disappointed that Ty's homecoming doesn't go as planned when he shows up with a female "friend" on the back of his motorcycle.
Nick Harwell is having trouble with his polo pony and Amy, Scott and Ty get involved. But will Nick's wealthy patron allow Nick to follow their advice? Meanwhile Lou is home for a visit. She's upset that the dude ranch has been neglected and Dubai may not be all that she thought it would be.
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. Chase shows up at the ranch and wants Amy to do a clinic with him. Ashley wants to host a birthday dinner for her Mother despite Caleb's misgivings.
As graduation looms, change comes to Heartland. Amy is offered a full scholarship at a university in Colorado. To Mallory's chagrin, Badger comes to work as a hand at the ranch. Lou and Tim arrange a deal to sell the dude ranch to Lisa. After several pointed suggestions from her mother, Ashley thinks about her future life with Caleb.
Peter returns from Dubai to find out what's going on with Lou. Sarah "Crazy" Craven's old horse is not well and Sarah brings it to Heartland. Mallory and Badger go back to the Craven place to feed the other animals but end up getting trapped there.
When Tim decides not to enter his horse in the big race, Janice his jockey/girl-friend agrees to ride for a competitor. Badger buys a car but finds out that its stolen and has to get rid of it before Jack finds out. When Soroya starts managing the dude ranch, Ashley wants to be promoted to manager at the café.
When Caleb needs some cash for a down-payment on his trailer lot he enters a team roping event. Amy is upset when he asks Kit to be his roping partner. Meanwhile Badger is trying to interpret the mixed signals he's getting from Mallory about their relationship status. Tim considers selling Lightning Dexter, his race horse, rather than keeping it through its convalescence period.
Amy is hired to teach a class of convicts about horse training as part of their work program. Ty is surprised when one of the cons turns out to be an old friend. Meanwhile Badger's summer at the ranch is coming to an end and he's upset that Mallory might just be using him in an effort to gain Jake's attention.
Lou comes back from Dubai to spend time with the family. Ty and Amy discover where her father's rustled cattle are being pastured and the whole family rides out to bring them back. Meanwhile Ashley's mother offers to give Ashley the lot that the trailer is on if she'll get Caleb to sign a marriage contract (pre-nup)
When an irate Grant, Ty's travel buddy shows up at Heartland to punch out Ty for "kissing Blair" the disclosure puts Ty and Amy's relationship in jeopardy. Meanwhile finding out that their marriage was not legal puts Caleb and Ashley into a turmoil. All the relationship drama makes Lou question her marriage with Peter.
Tim decides to enter his racehorse, Lightning Dexter, in claiming race despite Amy's objections. Amy and Ty's troubles are aggravated when Chase comes to town and offers to put in a bid on Dexter. Meanwhile Lou finds out that she's pregnant and though Peter comes home, he really needs to be in Dubai.
Jack resists taking a trip to France with Lisa while dealing with some old memories resurrected by remodeling Marion's room into a nursery. Caleb asks Ty to be his best man but has difficulty asking him to move out as Ashley wants. Amy agrees to be a bridesmaid at Ashley and Caleb's wedding.
Amy finds that she's over-committed when she promises to "de-sensitize" three horses for the local police. Deciding that she needs help she calls in Chase. Meanwhile Amy's returning the last of Ty's things throws him and when Jack discovers that Ty is skipping classes and not showing up to help Scott, Jack proposes a road trip.
When famous Olympic trainer Stewart Forrest hires Amy to coach his Olympic hopeful daughter, Amy feels that he's pushing her and her horse too hard. When Amy again gets Chase's help Ty is concerned. Meanwhile, Jack is concerned that Mallory is neglecting her horse, Copper. Lou discovers that while Peter is home with her, his business in Dubai is in crisis.
Everyone at Heartland is concerned by the bad publicity surrounding Olympic Trainer Stewart Forrest's lawsuit against Amy. Even Chase pulls his horses from Amy's training. Ty lends Amy his support and Lou does a little investigating. Meanwhile Caleb returns from his honeymoon alone. His wife, Ashley, has remained behind in Italy for an additional week with her mother.
Caleb's rodeo buddy Bryce returns from Afghanistan in a wheel chair and asks Amy to get his horse back into condition so that he can sell it. Amy would rather convince him to try riding again. Caleb's wife, Ashley has still not returned from Italy. Jack gets a call from the Foothills Cowboy Hall of Fame but it turns out it's not for what he expects.
Tim and his girlfriend announce that they are selling the ranch and moving to California. But one of Tim's old girlfriends comes back and claims that Tim is the father of her son, Shane. Ashley finally comes home. Ty is still having trouble just being friends with Amy. Ashley decides to go to school in British Columbia and Caleb is not sure if he should go or stay.
Ty and Amy take on a pair of Clydesdales with the help of Sugarfoot. Lou's water breaks while Peter is out of town. When a horse crazed boy and his mom show up at Heartland, Tim learns that he's got a son that he never knew about.