A FICTION HOUSE FACSIMILE REPRINT: Murder really shouldn't be taken too seriously. Spike Tracy, who has figured in several homicidal high-jinks, is all for good, clean, bloody fun, so if you haven't met him before, make his acquaintance now. He's an insouciant young man with plenty of money, good looks, and a sense of humor. The only blight on his life is his stodgy brother, R. Montgomery Tracy, the district attorney. His boon companion is Pug Beasley, a former bantam weight pug now in training to become a gentleman's gentleman in the Wodehouse manner, and there's a sister-in-law who goes in for committees and uplift. Oh yes, there's a murder, too. Don't giet impatient. Two of 'em in fact. It all starts when a beautiful woman stumbles over Spike's threshold one evening and collapses on his hearth. The next morning he reads that she's wanted for murder. His good sense tells him he ought to turn her over to the police and brother Richard. But Spike Tracy is not a young man who ever let good sense lead him astray. And anyway, he's sure brother Richard wouldn't appreciate her. Richard's that way. So, believing that the lovely woman who lies in his bedroom raving in delirium is guilty of murder, he sets out to make Richard and the police believe she isn't. If you insist on international spy rings, and rubies taken from the eye of a Burma idol, or blood spilling all over the lot, better pass this one up. But if you'd like a really intelligent mystery story, with a lot of fun thrown in, "A Most Immoral Murder" is your meat.