London 1925: after a grisly discovery in a ladies' rooming house, ex-boxer Harry Stubbs finds himself on a mission that takes him from the lowest dives to high society, searching for occult mysteries buried in the Horniman Musem, wrestling with enigmas - and bare-knuckle battling with deadly opponents. An insidious alien is at large, the time to stop it is running out - and that may not even be the worst of Harry's problems.