There are monsters in London - and ancient magic too.
In the sewers and on the marshes, in the Thames and the Serpentine, in Highgate and the Tower, in Westminster and Hampton, in the dark tunnels and in the earth.
It's unlikely that anyone will ever know, see, or feel their touch, but sometimes the monsters get restless and hungry.
Inspector Judas Iscariot, of Scotland Yard's secret occult-magic division, the Black Museum, has the unenviable task of ensuring that the Otherworldly do not stray into the world of the living.
Sometimes, however, evil finds a way.
Rumours start to circulate concerning a serial killer targeting angels, of ghoul gangs stealing children to order, and of dark forces searching for powerful magical weapons.
Detective Inspector Judas Iscariot investigates.
Is all Hell about to break loose, or will it be something far worse?