Matthew Hawkwood, ex-soldier turned Bow Street Runner, goes undercover to hunt down smugglers and traitors at the height of the Napoleonic Wars in this thrilling follow-up to Ratcatcher.

For a French prisoner of war, there is only one fate worse than the gallows: the hulks. Former man-o'-wars, now converted to prison ships, their fearsome reputation guarantees a sentence served in the most dreadful conditions.

Few survive. Escape, it's said, is impossible.

Yet reports persist of a sinister smuggling operation within this brutal world – and the Royal Navy is worried enough to send two of its officers to investigate.

But when they disappear without trace, the Navy turns in desperation to Bow Street for help. It's time to send in a man as dangerous as the prey. It's time to send in Hawkwood…