The year is 1941. The Nazis are sinking an astounding percentage of British Trans-Atlantic ships. Their abilities to ascertain where these ships will be and when their escorts will leave seems almost... supernatural. Enter our hero Duke de Richleau, who is able to convince one man in the British Intelligence that they may be battling not only earthly but astral enemies, able to see things during out-of-body experiences while asleep. These would include sealed mission plans for the British navy. Duke and his cluster of stiff-upper lip heroes eventually trace the threat to Haiti and a powerful witch doctor.
More weird things figure into this very readable stew, sure to whet the appetites of fans of vintage pulp or horror: voodoo, reincarnation, zombies, poltergeists, et al. Even toss in an appearance by Pan.
Wheatley is effective in setting the stakes as extending beyond mere life and death, and wastes no opportunity to tell readers of the wanton cruelty of which the Nazis and their allies were capable, cruelty going beyond this existence. He is able to sustain tension and thrills through real affection for the characters and their plight, and through the capacity for sadism of the villain, who is revealed late in the book, although one might guess earlier.
The couple of action scenes get the heart pounding, including one where the heroes are carrying a corpse to properly lay it to rest but are chased by a Haitian mob through a ghetto. Another is a chase in the astral plane that would be very fun to see through modern movie magic, as combatants turn into wasps, snakes, squids and more in rapid succession.
Other scenes are fun in a way Wheatley may not have intended, as our heroes must keep themselves from falling asleep, since they were lacking sufficient magical protection for the astral battles they knew would ensue. These are exciting in their own way, but there's something comical about a lengthy suspense scene revolving around staying awake all night.
On the negative side, this is perhaps 50 pages too long, which may sound like a lot, but it reads faster than that. It's just that Wheatley takes us down several paths that, while not uninteresting, could have been excised or summarized without any loss to the narrative. Additionally, Wheatley's writings are very propagandist and racist, especially toward native Haitians.
As far as plot, it holds up well as pulp fantasy horror, although there seemed to be one instance of fudging the astral "rules." You be the judge.
Some reviewers object to Wheatley's recurring demonic themes. It's not that Wheatley is pro-Satan or anything; his heroes are on the side of the angels, so to speak. But the devilish rituals are described with such attention to detail, and his protagonists combine so many of the world's "good" religions into one type of claptrap, that there may be enough to put off almost anyone's sensibilities. Still, this particular book has less to offend than many of his other works (you'll generally know by their titles). Some may otherwise object to the didactic tone, but if you find the subjects interesting, you likely will not be bothered.
In the final analysis, the main question to ask in determining a book's quality is if it makes one want to read more by the author, and Strange Conflict did so for me. Perhaps I shall try Star of Ill Omen next.