Watchers (1988)

A spirited golden retriever survives an explosion at a secret government lab and makes its way to the suburbs, where it is taken in by Travis (Corey Haim), a lonely teenager. Travis quickly discovers that the dog is highly intelligent and is able to use the English language. A ruthless government agent named Lem (Michael Ironside) is out to retrieve the animal, as well as another mutated beast that was released in the explosion and has since embarked on a murderous rampage.