Guards! Guards! a Discworld graphic novel

"A seventy-foot-long fire-breathing dragon is wanted to help with enquiries into the identity of the night-time prowler who is turning the citizens of Ankh-Morpork into something resembling small charcoal biscuits, and the only thing that can prevent the inevitable destruction of the city are the drunken and world-weary Captain Vimes and his forgotten police force -- an overweight and cowardly sergeant, a corporal who just about qualifies as human, and the Discworld's tallest dwarf..."--Back cover.