Detective Inspector Sebastian Thumbs has just been promoted on the London police force when he and his partner, Joseph Atwell discover the body of a mellified man. The victim has been turned into a hive for honey--and a mechanical queen has been lodged inside his chest cavity. The case develops when both detectives realize their victim was pierced by a stinger in the back of his neck, turning him into a drone, and giving him no free will.

When more bodies with different bugs and mechanical creatures show up, the desperate detective team seek the help of a phrenologist, Phineas Hoffsteadr, to understand the true nature of the men killed. As his relationship with Phineas develops, Sebastian soon realizes that there are some things history--and himself--cannot repress.