"In 1565, he seized Allan Stewart, the Commendator of Crossraguel, and imprisoned him at Dunure Castle, seeking to obtain from him certain of the rights over the lands of Crossraguel Abbey.For two days he was left to consider his fate, when Stewart proved recalcitrant, Cassilis had him dragged to the Black Vault of Dunure, and roasted him alive over a fire until he was willing to subscribe to the charters the Earl had drawn up.