Tortured Souls

When the call to evacuate the City came, many people simply missed it, the homeless, tourists, or, those simply in the wrong place at the wrong time.
Many others underestimated the scale of the threat, choosing instead to wait out the crush of panicked individuals fleeing the City or were members of the support services too dedicated to leave.
Then it happened, The Event, a vast explosion of other-wordly energies that that tore through reality
Most of them weren't even aware that they had been altered/infected until the change had begun. 
Of course, by then it was too late.
Driven by the savage need to fuel the evolution of their host body, they hunt.
Preying on the survivors of the cataclysmic blast, the shattered streets of London have become home to soul stealing  nightmare creatures.

Don't let them take you alive