Calcutta 1837. The East India Company rules India – or most of it; and its most notorious and celebrated son, Xavier Mountstuart, has gone missing.

William Avery, a down-at-heel junior officer in the Company’s army, is sent to find him, in the unlikely company of the enigmatic and uncouth Jeremiah Blake. A more mismatched duo couldn’t be imagined, but they must bury their differences as they are caught up in a search that turns up too many unanswered questions and seems bound to end in failure.

What was it that so captivated Mountstuart about the Thugs, the murderous sect of Kali-worshippers who strangle innocent travellers by the roadside? Who is Jeremiah Blake and can he be trusted? And why is the whole enterprise shrouded in such secrecy?