<p>Summer 1914. A London-based private detective, Sergeant Dagger, is employed by Celia Harrison, a suffragette, to discover why her husband, an army Captain, has committed suicide. Unconvinced by the official verdict of <em>melancholia</em>, Celia wants the truth - as do MI5, who also recruit Dagger.</p><p>As WW1 breaks out, Dagger reluctantly joins the British Expeditionary Force, and sails to France with the first battalions. There he uncovers a web of deceit and hypocrisy lying at the heart of the British Army.</p><p>Operating along the fast-moving front-line, Dagger sees the death of the first British soldier, flies with the Royal Flying Corp into occupied Belgium and fights at the Battles of Le Cateau and the Aisne.</p><p>Later, reassigned to libertine Paris, Dagger, an amateur artist and poet, meets modernist icons Picasso, Cocteau and Apollinaire before discovering the identity of a mysterious painter called Fevert and helping MI5 solve one last problem.</p>