Nobody dreams up more colorful names than Burke. In Dave Robicheaux's latest case, the New Iberia, La., detective crosses paths with insurance huckster Cash Money Mouton, smut peddler Fat Sammy Figorelli, and brutal prison guard Cain't-See to Cain't-See Double-Time Strunk. Burke crafts equally vivid descriptions of these lowlifes (Mouton ''smelled of deodorant, hair tonic, and fear''). But the plot strains to link a legendary bluesman's decades-ago disappearance, a teenage girl's drunken-driving death, and an alleged IRA hitman's plan to whack a priest during confession. While ''Last Car'' ultimately careens into convolution, it's still an enjoyable ride.