Yes, it’s another Fandorin novel! This one was first published in Russian in 1999, and is the sixth to be translated into English.
The story starts with the assassination of the not all that popular General Khrapov just outside Moscow, with the added bonus of the assassin posing as Fandorin. Once that misunderstanding is out of the way, Fandorin finds himself in the middle of a power struggle with deceit and betrayal all around. Who is giving information to the revolutionaries, and why? Is there anyone Fandorin can trust?
The viewpoint alternates between Fandorin and a revolutionary known as “Green”, which adds a lot – seeing everything form two wildly conflicting angles makes the whole story more interesting.
It’s all good fun, with enough misdirection to keep most readers guessing for a long time. If you haven’t read any of the earlier books, there’s no harm in starting here. Then you can go back and read the other books.