Black O'Malley is a character who appears in Halt's Peril.
O'Malley is feared by a vast amount of people due to his temper and intelligence, making him a foolish man to cross to the ordinary commoner.
Will and Halt interrogate him at the beginning of the book to discover Tennyson's location (Picta) as Will has discovered that it was where Tennyson and his cohorts fled to after the events of The Kings of Clonmel. Will is unable to get him to talk, and O'Malley takes one of his gold coins. After Will's unsuccessful attempt, Halt is able to get him to reveal the information. He later attempts pursuit of Will and Halt in his ship. The Claw, Black O'malley's ship, was wounded in the fight.
Black O'Malley's name comes from the black scar that mars part of his face, during a fight, a torch struck O'Malley and the burning pitch left a permanent black scar.