The death of Achilles - B. Akunin

International intrigue, professional rivalry, the criminal underworld of nineteenth-century Moscow, and an irresistible femme fatale: if Erast Fandorin was hoping for a quiet homecoming, he is about to be disappointed.
Erast Fandorin returns to Moscow after an absence of six years, only to find himself instantly embroiled in court politics and scandal. His old friend General Sobolev - the famous 'Russian Achilles' - has been found dead in a hotel room, and Fandorin suspects foul play.
Using his now-famous powers of detection - powers that belie his twenty-six years - Fandorin embarks on an investigation, during which the political and the personal may become dangerously blurred. With the assistance of some formidable martial arts skills, acquired whilst Fandorin was in Japan, our eccentric and ingenious hero must endeavour to discover not so much whodunit, as why ...