Butkus lived in a cage while waiting to be sold at J&M Tropical Fish. Rocky displayed a lot of love and affection for the dog as he would usually yell "Yo, Butkus!" and make animal noises during his routine visits. Butkus was later given to Rocky by Adrian as a Christmas gift to keep him company while training for the Heavyweight Championship of the World. Rocky and Butkus were later seen running down the street together on their way to the meat plant where Paulie worked. After noticing a news truck parked by the plant, Rocky left Butkus on the street to wait for him while he went inside to satisfy his curiosity. Butkus is not seen again for the rest of the film.