- "I once knew this geezer called Onslow in the Isle of Dogs in East End, London. Leary little scallywag, he was to smart by half, never trusted him."
- —Alfred Pennyworth about Onslow
Onslow was a childhood acquaintance of Alfred Pennyworth.
Alfred Pennyworth and Lucius Fox met in a Gotham bar. Upon shaking hands and introducing themselves, Mr. Fox mentioned his name was Lucius. Alfred started telling the story of Onslow. Describing him as "a leery little scallywag" and that Alfred couldn't trust him. Alfred noted that Onslow approached him asking for an iffy favor, which judging by Alfred being defensive may well have been petty larceny. Alfred agreed but told Onslow that if he let him down he would tuck him up like a kipper. Onslow swore upon his mother's grave he'd never do such a thing, but he did. So Alfred tucked him up, like a kipper.
- "Rise of the Villains: Knock, Knock" (mentioned)