Hells Marauders, The Demon Siege

The Prayers to Cthulhu, though destroyed in the battle at Mother Mary's Church, left behind fragments of its arcane power. 

In the shadows of London's underground tunnels, a cultist—once a disciple of Lovecraft's duplicate—has recovered a shard of the cursed tome. 

This fragment, infused with residual cosmic energy, begins to summon whispers from beyond reality..from Cthulhu!