Young Timmy Martin's world falls apart when he learns that his family must move to Australia. Lassie is to remain in America, so the Martins search for a new home for the Collie. Neighbor Cully Wilson takes Lassie in, but the old man already has a dog, the cheeky Yorkshire Terrier named Silky. Lassie is now constantly occupied with keeping the small dog in check.
| Actor | Role |
|---|---|
 LassieLassie the Dog | Lassie the Dog |
 Robert BrayRanger Cory | Ranger Cory |
| JJune LockhartRuth Martin | Ruth Martin |
 Jon ProvostTimmy Martin | Timmy Martin |
| HHugh ReillyPaul Martin | Paul Martin |
| AAndy ClydeCully Wilson | Cully Wilson |