"Possessed by Evil" begins with the summoning and tells the tale of Tom, a prisoner, as he is overtaken by a demon and experiences a string of horrific incidents. Tom starts to explore the strange realm as his situation gets worse and despair settles in, learning new things about himself and the demons that possess him.
Tom points out the growing struggle for dominance between good and evil. Tensions increase as demonic allies appear and Tom descends further into the pit.
The implications of Tom's possession and the evil that kidnapped him are discussed in the story's epilogue. The entire storyline develops from a straightforward arrest to a challenging and horrifying story about Tom and his struggle against demonic corruption.