Show-biz novels are full of pitfalls, especially when the story depends on evocations of actual performance. And, unlike the best work by Larry McMurtry and Don Carpenter, this uneven third novel by Texas writer Smith (Country Music, Thin Men of Haddam) can't quite overcome those obstacles--while its non-show-biz aspects are marred by excess sentimentality. Don and Dottie Baxter are a singing/playing/comedy duo on the Holiday Inn circuit--but now they're heading for their first gig in Las Vegas: doing intermissions for the headlining lounge act of a big casino. ""There's a ladder, and the Vestal Virgin Room is like skipping up a half-dozen rungs at once,"" says Don. Dottie (who also narrates, in alternating chapters) is much less enthusiastic, less ambitious: nearing 40, she wants a child--to replace the daughter who died in a freak accident just a few years ago--while Don, obsessed with the act, is terrified of being a father again, risking another terrible loss. So, as the duo drives toward Vegas, nervously preparing for the big opening, there's lots of tension--with nervous/brash Don still caught between ambition and festering grief, Dottie wary about both the near and distant future. (""Until now, I've been anxious about what might happen if we do well there, what it might mean in terms of our being a family again, but now I suddenly shiver with a new horror: what will happen to Don, to us, if we don't make good?"") Unsurprisingly, then, the Vegas opening becomes a nightmare: the act is barely noticed, a bigtime agent walks out, Dottie gets fed up with Don's obsession. (""He believes in this crap so much I wonder if he'll ever be able to see that his dream will never materialize."") After a fight, Dottie goes home to St. Louis, works at the library, has an affair, gains some independence. Don, meanwhile, scrounges for show-biz work, misses Dottie, has despairing sex: ""Five minutes of riding Sheila had ruined the moment when Dottie and I conceived Amy. I didn't know it was holy until I had desecrated it."" And there'll be a St. Louis reunion at the fadeout. . .a bit saccharine if not entirely optimistic. Smith does well with most of the surfaces here: the on-the-road seediness, an inane radio talk-show, the Vegas anomie, plump Dottie's self-consciousness, and the day-to-day conversational texture of a marriage in trouble. When reaching for deeper heartache, however, he usually comes up with maudlin clichÃ‰s. And the whole novel is skewed by Smith's moment-by-moment presentation of the couple's act: it is so terrible (not the intended effect, perhaps) that it's difficult to take Don's ""dream"" even half-seriously. More pathetic that dramatic, then, without enough genuine comedy to balance the dreary soul-searching.