Garth takes Jimmy Fredericks back to the ranch. There Jimmy meets Lucy Baker, deaf most of her life, and her pet wolf Mountie. Unfortunately while he's playing with Lassie, Mountie is shot by a shepherd who doesn't know he's a pet.
Boone Sawyer has a unique ability to communicate with nature while protecting the animals. When hunters swear out an assault complaint against Boone, Lassie visits with him while Corey searches for a solution to his problem.
Timmy and his classmates buy a baby elephant to donate to the local zoo without acquiring the proper city authorizations so the Martin farm must house the animal for an unknown duration.
Nancy is a physical therapist who uses tree planting to help her patients, four children who are disabled. Corey and Lassie arrive to assist her with the kids who respond eagerly. Jimmy is the exception who is depressed about his limitations.
Dusty, a lead pack mule, is being retired but he doesn't want retirement. Instead, he breaks away and follows his pack team with Lassie close behind him. His persistence convinces his human to let him continue packing.
Delivering trees on Christmas Eve, Lassie and Corey find and free a dove tangled up in brush. The dove repays the favor by leading Lassie to a little girl's lost puppy so that Lassie can return it to the worried child.
When land is being cleared and burned to create new grazing land for cattle, Lassie plays protector to a family of rabbits caught in the upheaval. She helps them relocate and protects them from predators during their move.