Kris Furillo (Genevieve Cortese), having just served time at juvenille detention center for grand theft auto and resisting arrest, is offered a job at the Ritter family ranch after Pablo Betart (Greg Serano), a center volunteer who teaches inmates to ride, notices Kris' unusual talent with horses especially the horse Wildfire, with whom Kris has bonded.
The fourth season begins six months after Kris was forced out of Raintree, which has undergone significant operational changes that leave Matt pining for the past.
Kris and Junior help Matt with his improbable plan to get Raintree back in the horseracing business, which involves finding Wildfire's offspring, Flame.
Junior's preoccupation with his and Calvin's business proposition takes time away from his wedding plans, but Laura suspects his loss of focus may have something to do with Kris.
Kris hopes that Flame's success in the DuPont Stakes might help Jean change her mind about Raintree's future, but Kris isn't so sure about what part, if any, play in it.
With Jean still out of commission, Kris and Matt do their best to run the dude ranch at Raintree while also preparing for the next race, which features Dani's new horse in the field.