No one would know about this book if it wasn't for the 80's scif-fi horror flick 'Lifeforce' (starring the very beautiful and very naked Mathilda May) which was based on this novel.
As always, the book is better than the movie, and if you are a big fan of the movie, as I am, (most straight men should be), then I highly recommend the book it was based off of. The most intriguing element for me is the scientific explanation of vampires, and examples of vampiristic creatures such as the moray eel. The origins of these creatures are not explored at any great length, but the detailed scientific elements make the story believable. The explanations of vampires in this book remind me of H.G. Wells' 'First Men in the Moon' when Cavort is explaining the scientific basis of cavorite to Mr. Bedford.
This is also a short book and an easy read. There's nothing too groundbreaking here, so I won't give it five stars, but it is still an enjoyable read. Anytime I meet people who are fans of science-fiction, I always point them to 'Space Vampires'.