Set 30 years in the future, HELLGATE: LONDON introduces players to a world devastated by a demonic invasion where mankind has gone underground to survive. The Cabal is an organization that brings together the disciplines of fringe science and arcane practices in order to unleash the inner potential of Mankind's spirit. As the Templar seek to protect the world from the forces of darkness, Cabalists come together to study it. Some yearn for the promise of power while others hold true to the axiom of keeping their friends close and their enemies closer.

Delvers of arcane knowledge, students of the dark arts and explorers on the edge of science, Cabalists are HELLGATE: LONDON'S spell-casters. Summoners of demons and controllers of primal forces, Cabalists use the demons' own powers as a weapon to stave off the forces of Hell. Using "black" magic and arcane weaponry as their primary means of battling the demonic hordes, they literally fight fire with fire and blood with blood. Some have been so touched by the dark forces they wield that they even display the traits of their enemies, ever riding the razor's edge between good and evil, control and corruption.

The spells of the Cabalist fall into three schools. Summoning spells allow the Cabalist to capture, control and even train the minions of Hell. When invoked, these powers summon demons from the netherworld and force them to fight against their kindred. Spectral spells summon dark forces from the spectral plane, which can cause colossal damage to any enemy. Transformation spells bestow the Cabalist with greater powers by modifying their appearance to mimic demonic characteristics such as horns, spikes, claws and elongated limbs.