Darnell Rudner, also known as Spyder, is an inmate at the San Juan Correctional Facility.
Rudner's first arrest was as a juvenile in 7th grade for an unspecified crime. He was later convicted of four murders, though it is suspected that he may have been responsible for more, and is serving a near-life sentence with possibility of parole in 50 years. Nicknamed Spyder, he is extremely violent, known to brutalize people on a whim and just finished a stint in solitary for attacking another prisoner for touching his possessions. Adrian Monk, going undercover as Ben Lincoln, becomes Spyder's cellmate to find some clues in the murder of Ray Kaspo, having heard from Miss F., the prison librarian, that the two shared cells in Calgary. Although initially hostile, Monk gains Spyder's respect and even warms up to him in due time. When Spyder's heirloom wristwatch is stolen, Monk retrieves it from Lody, leader of the prison neo-Nazi gang, after deducing from his rolled up sleeves and height that he must have been the one to snatch it from his shelf. When the neo-Nazis come back for revenge, Spyder saves Monk's life from certain death by beating Lody and his assailants back. Though the tip-off turn out to have been a lie, Sharona solves the case, successfully identifying author J.T. DeMornay and his mother Sylvia Fairborn as the culprits.