Don't Know Jack

Don't Know Jack is a criminal from Sto Lat, referenced in Thud!. it is possible he is the polar opposite of Done It Duncan, as the phrase Don't know jack... is slang shorthand for "I don't know nuffin'", suggesting the sort of character who is temperamentally opposed to Helping The Watch With Their Inquiries. Inquire at places like the Urban Dictionary for the full version of the colloquial phrase don't know jack....