On a surveying mission of the forest, Scott and Bob are delighted to find wolves restablishing themselves in the area. Then the male is shot while hunting for his pregnant mate and the rangers must save him--and change the hunter's mind about wolves.

During a surveying trip at a former bombsite sleighted to become a national grassland, Scott carefully disarms the unexploded bomb next to a trapped man while Lassie shuttles supplies to him.

Widowed Sarah Caldwell will have to give up the family ranch if she can't keep water on the property, so Scott helps her install ""water bottles,"" large vinyl storage ""tanks."" But a thirsty fawn gets himself trapped inside the slippery containers.

As they take an elk survey, Scott and Lassie's helicopter ride turns deadly when the vehicle has has mechnical problems and crashes in the snowy wilderness. Bert tries to at least fix the communications system, but that too is beyond hope; they must rely on their survival gear and wait for rescue.

While surveying Government rangeland, Scott is hurt by a careless rifle shot fired by young Tom Bradley, a boy who has taken to playing hookey and staying in the woods after his mother's death; later, another shot of Tom's gone wrong injures his father.

Neeka, spending his vacation with Scott and Bob, is delighted to help the rangers out at the Roaring Camp spur line, a railroad that will run directly through the majestic redwood forest. There they befriend a persistent little bantam chick (Neeka names him Fairbanks) who is constantly wandering into trouble.

On a nature hike, Scott and Lassie help Kathy, a withdrawn and fearful girl who is attending school with other blind children for the first time.

Scott and Lassie help a doe who has been chased to exhaustion by snowmobilers.

Scott and Lassie, in San Francisco's Chinatown for a mini-forest project, befriend the children in a Chinese school. Lassie is struck by a car while saving one of the children and appears to have amnesia. So when a fire strikes the vet's office she's staying at, she escapes to the streets with no idea where she belongs.