Cycle of Fear: There Is No End (2008)

Horror - One year ago, fourteen teenagers went missing without a trace. Days later, Tabetha, the only survivor, is discovered with no memory of who she is or what occurred. Two ancient enemies from beyond the natural world race to find Tabetha and the secret(s) she holds, guiding them all to a codex able to protect humanity and the world from the Seven Gates Of Hell. - Valerie Morrissey, Rachael Ancheril, Sean Kaufmann