I´m in process of detailed re-reading of Creatures Anathema and in several entries I read about heretical group/cult/philoshopy of Denialist. They are almost exclusively listed as panic and riot spreadining bands feeding on strife created by other subjects and fall of Imperial society into anarchy (at least once, they are directly put side by side with apocalypse preaching Redemptionist).
Could anybody point me at more coherent piece of backround which describe them, or are they just a random mentions through the CA?