The Thornton District Specter

After a very powerful Specter materializes within the Thornton Police District taking people’s lives as prisoner spirits for its sick pleasure of terrible torment all attempts at Exorcism fail miserably. Clairvoyants, White Witches, Parapsychologists and the local Police Inspector all join forces then to find a method to eradicate it. They then find this Evil Entity almost as powerful as the Devil itself.
This Specter had so far caused the deaths of some twenty people. The modus–operandi it had used was always very similar. A lone driver late at night would suddenly find this Specter sitting next to them obviously seen in its most terrifying form causing the driver to lose control of the vehicle and crash causing their death.
The only reason this was known was after a very high rate of unexplained local area single fatal vehicle crashes there had been a lone survivor. At first police were highly skeptical at the shocking story they were told by the driver at the scene, however after their own crash investigators eventually found there was no environmental explanation or vehicular fault causes for the high rate of fatal crashes in any of the cases they wondered if there just might be some truth in it? It did explain a lot if what the surviving driver said was in fact true. All drivers had either unexplainably run off the road into trees or rolled their vehicles after swerving madly as if trying suddenly to desperately escape.
Three Clairvoyants that had been called in previously with some success in looking into old unsolved crimes of murder in the area before closing the books on these crimes were again called in by the local Police Inspector to hopefully track this Specter down, find out who, or what it was and why it was so intent on murder of people who appeared to be total strangers of each other. Had any of these people done anything to it when it was human? That’s if it ever was human. Why was it taking lives in the Thornton District?
Contact then by the Clairvoyants of a victim’s spirit at a crash site leads them via visions to an old derelict Manor where further investigations find the very powerful presence of the Specter in its lair.