The Death of Achilles (Russian: Смерть Ахиллеса) is the fourth novel in the Erast Fandorin historical detective series by Boris Akunin.

Fandorin further discovers that the plot leads up to the highest levels of the Tsar's government, and that he himself is now viewed as an enemy of the state for his efforts to catch the killer.

The second half of the novel is told from Achimas' point of view and recounts his life story, up to the plot to kill Sobolev and the investigation.

By chance, Achimas discovers that the man who hired him to kill Sobolev was Grand Duke Kirill Alexandrovich, the younger brother of Tsar Alexander III.

Apparently, the royal court came to perceive Sobolev as dangerous due to his Napoleonic ambitions, while his immense popularity among the people makes an open trial impossible.

In the concluding chapters of the novel, Fandorin kills Achimas, and prepares to flee Moscow (believing himself to be a target of the plotters), but Prince Dolgorukoi's assistant meets him at the train station and tells him that everything has been covered up and he can continue in the service of the state.

Welde's career also includes an episode touching on a Belgian paedophile serial killer, reminiscent of the real-life such affair in Belgium a century later than the time in which the book is set.

The press reports regarding his demise was heavily censored which gave rise to many conspiracy theories, some implicating the Tsar Alexander III himself.