'The Ka of Gifford Hillary' is one of those books which despite being rather absurd is a compulsive read. But this can also be said of Dennis Wheatley's other occult novels. Great entertainment value, but little in the way of believability.
In this book we have a wealthy man, Sir Gifford, who finds that he has an 'out of body' experience in the most literal sense. His spirit, or 'ka', has escaped from his body and wanders around southern England (...don't ask! these things just happen :-)). Actually the circumstances behind this (murders and mayhem) are rather interesting, as is Sir Gifford's efforts to get his ka back into his body. (...remember, I didn't say this book ranked high on the believability index) At any rate, the story does move at a quick pace and does have some entertaining/interesting moments, especially in the end.
Bottom line: certainly an odd fish in the world of literature. But Wheatley was like a Stephen King from our father's (or grandfather's) generation, so his works deserve some respect. This even includes 'The Ka of Gifford Hillary', a quirky fable which is only 'average Wheatley' (best left to Wheatley fans only).