Deep in the trenches of Flanders Fields, men are dying in their thousands. So one more death shouldn't be a surprise. But then a body turns up with bizarre injuries, and Sherlock Holmes' former sidekick Dr John Watson finds his suspicions raised. The eyes are almost popping out of his head, as if the man had seen unimaginable horror. But this is just the beginning. Soon more bodies appear, and Watson must step out of the shadows into the limelight if he's to solve the mystery behind the inexplicable deaths.