This is the third entry in the series. The first two are “The Image Of The Beast” (1968) and the second is “Blown” (1969). The first two were published as porn but this one is totally different. This one is about a device called MEDIUM. Use it for a big fee and you can talk to the dead. Private Detective Herald Childe returns but now he has a new name, Gordon Carfax and he’s a history professor.
Gordon is once again a P.I. thanks to his cousin Patricia. Their cousin Western has taken credit for MEDIIUM. She says her father Rufton was the real inventor and accuses Western of murdering him and blowing up his house destroying any and all evidence. Of course he manages to rob the safe of all schematics so he could build it himself.
Gordon has been on the lecture circuit saying the contacts made with MEDIUM aren’t the dead but possibly aliens from another universe who can mock humans.
Gordon meets with Western and has a session with MEDIUM where he tries to talk with his uncle Rufton. The entity seems to charge out of the machine and Gordon freaks and runs out of the room. Patricia tells him of a medium named Mrs.Webster who seems legit and they take part in a seance. That doesn’t go too well either.
A group consisting of various religious leaders uses MEDIUM to see if it’s the real thing. A bishop dies of a heart attack after talking with a playmate he had when he was eleven. Mass trouble begins. An atheist flies his plane into the building and destroys MEDIUM.
The book turns into an action thriller as bullets fly and more things blow up. Gordon and Patricia try and track down Western and solve the mystery of MEDIUM. They also discover what other experiments their cousin had in mind. A Senator gets involved when they find out MEDIUM can be used as a cheap source of power that could put utility companies worldwide out of business.
The thriller aspects are the main parts of the novel with SF mixed in. If you’re looking for an action novel as opposed to a SF story then you’ll probably like this one.