Poet-novelist Butler (Jujitsu for Christ, 1986) tries his hand at science fiction, with a curious though often rewarding blend of old and new ideas: vampires on 21st-century Mars. Two huge Martian craters have been terraformed, roofed over with transparent plastic, then warmed and watered. Among the colonists is reclusive John Shade, vampire and ex-US secret agent (Americanized Earth is now known opprobriously as ""Sam""). As Shade experiences the familiar craving for blood, he's approached by the mysterious Benjamin (who seems lo know all about Shade) to lead a revolt against Sam's oppressive neocolonialism and the huge utility companies that own Mars. Helping Shade will be Mandrake, an advanced Artificial Intelligence, and Jennie, a ""jangler"" (she's had her organic brain replaced with a computer). So, blood-lust satisfied upon a traitor (maybe!), Shade puts together a small, deadly strike force, and wreaks havoc--until he unmasks a traitor, realizes how he's been manipulated, and discovers that poor Jennie was used and destroyed simply to attract Shade's attention. Scientifically impressive, with lots of likely extrapolations (though the janglers don't sound or act much different than regular folks), one or two new vampire wrinkles. and a well-thought-out if overinvolved plot. The upshot would be easier to warm lo if the writing were less obtrusively clever and self-congratulatory.