Knuckles is the tertiary antagonist in the 2014 film The Nut Job. He is King's sidekick that doesn't speak. Despite his hearing problem he can also hear the dog whistle, which somehow irritates him.
The Nut Job
Knuckles was seen at the Nut Shop being introduced by King. The next morning, after hearing the dog whistle, he gets fed up with it, snatches it and threw it out the door, only to be retrieved by Surly. Later on, during the climax, he and King betray their partners by replacing their bags of stolen money with nuts. After the dam burst, Knuckles, King, and the animals were stranded on the river, near a waterfall. While Raccoon was trying to kill Surly, Knuckles took the bags of money and tried to move the truck away, only to get affected by Surly blowing the dog whistle, and falling off the log. In the end, he was seen being arrested.