Wikipedia
Necroscope
Necroscope is the title of a series of horror novels by British author Brian Lumley.
The term necroscope, as defined in the series, describes someone who can communicate with the dead (coined Deadspeak later in the series). Unlike necromancers, who here extract the knowledge they seek by brutal eviscerations of corpses, a necroscope can communicate with them as equals: peacefully and without any physical interference. The abilities of a necroscope are defined as a type of ESP.
Necroscope (novel)
Necroscope is the first book in the Necroscope series by British writer Brian Lumley. It was released in 1986.