Capitol Offense,<i> By Barbara Mikulski and Marylouise Oates (Dutton; $23.95; 312 pp.)</i>

“For the next two weeks, I could barely keep track of all the advice people wanted to send my way. A few even came up with some actual information. Naturally, not everything I heard made me happy. On Thursday night, the Senate finally wrapped up several 12-hour days. . . . At first, the whole legislative battle was exciting. Then it became exacting. Finally, it reached the exhausting pain-in-the-neck state. I stumbled into my apartment long after the dinner hour. . . . I’d poured myself a glass of nice Chianti, plopped some diced onions and celery from the plastic bags into a pan with dash of olive oil, and was happily chunking up a passable eggplant. I popped the play button on my answering machine . . . when I heard the unfamiliar voice put in his two bits, ‘Norie, Norie Gorzack. You better watch out, you know. You’re treading on dangerous ground. . . . But the guys from Nam, guys from Delta Force, know you’re up to the job. . . .’ I played the recording through two more times, and then went back to my eggplant.”

****

If real-life Washington is not weird enough for you, Maryland Sen. Mikulski and D.C. writer Oates (a former staff writer at The Times) serve up this Senate cloakroom who-done-it potboiler novel. The book is timed for release at the Democratic National Convention, where other variety of suspense is apt to be in short supply. The characters are thin, the cliches thick, the kitchen asides overdone, but the pace is lively: A newly appointed woman senator confronts cynicism in the Senate staff, arrogance in the seniority system, the murky politics of MIAs, and people who keep turning out differently than you expect and sometimes end up dead.