Voodoo recycling

Here's a publishing oddity. Two novels with different titles, different authors and different heroes... and yet the overall plot and most of the events are almost identical. First we have Sexton Blake Library no. 496: Come Dark, Come Evil by Wilfred McNeilly, published in March 1962. Then there is Dark Ways to Death by Peter Saxon (1968), the second book in a series featuring a group called The Guardians. "Peter Saxon" was a house name used by several different authors, McNeilly among them... so this is presumably a case of McNeilly recycling his own material rather than any kind of plagiarism.

The original version is actually quite good, with Sexton Blake and his team pitted against a voodoo cult who carry out their rituals (including human sacrifices) in disused tunnels of the London Underground. There are hints of occult powers at work, but in the end it's all wrapped up with a neat rational explanation for everything. The Snake God worshipped by the cult turns out to be a rich industrialist who has become obsessed with the "left-hand path".

The problem with the later version is that (unlike Sexton Blake) the "Guardians" books are science fiction: the Guardians themselves have paranormal powers, and their job is to battle occult forces. There's nothing wrong with that, of course, as long as the occult forces are the only possible explanation of what goes on, and using paranormal powers is the only possible way to resolve the story. But the existence of the first version proves that neither of these is the case! It was a perfectly good story with a perfectly satisfying ending. To make it fit into the Guardians format, McNeilly has to make the Snake God a real Snake God, while the rich industrialist obsessed with the left-hand path (who is still in the story, for some reason) is just a harmless eccentric!