For the audio diary with the same name, see Knuckles (Audio Diary).
I SWEAR I saw Knuckles today, in one of those diver outfits. He had that same gimpy walk… I went up to him, and he wasn't screamin' no more… he was kinda cryin'
― Louie McGraff[src]

Knuckles is a friend of Louie McGraff who served time with him in Persephone. One night, while Louie was asleep, Knuckles was taken from his cell. Later on, Louie noticed scientists dragging a Big Daddy suit elsewhere. Soon after, he heard horrifying screams and determined that the screams came from Knuckles.[1] After McGraff was freed, he encountered Knuckles in person, identifying him by his "gimpy walk." Knuckles had become a Big Daddy and all he could do was cry.[2]


  1. Louie McGraff's Audio Diary: Strange Goings On
  2. Louie McGraff's Audio Diary: Knuckles