Notes:
It's atypical for The Flash, who was a science-oriented character, to be involved in a supernatural-themed tale.
Also, why isn't he visiting his buddy, Jay Garrick (the Golden Age Flash), instead of The Spectre, who at this point in time, The Scarlet Speedster had only seen during the annual JLA/JSA "Crisis on..." summer team-up ("Crisis Between Earth-One and Earth-Two!"/"Bridge Between Earths!") and never even spoken with?
(They were in the middle of a pitched battle with the Anti-Matter Man!)
Visit Amazon and Buy...
Wrath of the Spectre
Omnibus
(which reprints all The Spectre's Silver and Bronze Age Appearances...in color, which the black-and-white Showcase volume doesn't do!)