Michele Martinez initiates a very subtle change of direction in COVER-UP, her third Melanie Vargas novel. MOST WANTED and THE FINISHING SCHOOL, the first two books in the series, introduced not only Vargas but also a plethora of secondary characters that included several members of Vargas's personal family and circle of co-workers. In COVER-UP, Martinez moves a majority of the characters (Vargas's mother, sister and boss, among others) to the side --- if not off the board entirely --- giving a freshly-divorced Vargas and her blossoming relationship with Dan O'Reilly the opportunity to sparkle.

COVER-UP begins with Assistant U.S. District Attorney Vargas being pulled reluctantly into the lead of the investigation of the savage murder of Suzanne Shepard, a television reporter who has a high Q rating with the viewing public but receives low marks from her prospective targets. Vargas has no shortage of suspects, who range from a celebrity personal trainer to a Park Avenue nip/tuck surgeon to --- most significantly of all --- Clyde Williams, a New York City councilman with designs on the mayor chair who also happens to be the father of one of Vargas's best friends in the office. When Vargas does not immediately bring charges against Williams, Shepard's network screams cover-up, which does not help Vargas's investigation.

Meanwhile, FBI Agent O'Reilly is his usual competent self --- both on the job and between the sheets (functions that, as readers shall see, he sometimes performs simultaneously), though his increasingly frequent nighttime disappearances are giving Vargas pause. To make matters worse, it appears that the killer is now tracking Vargas to the extent that he knows her every move despite her own best efforts.

Suspects are ruled in and then out, making COVER-UP a classic and suspenseful whodunit, even as Vargas races to a fateful and climactic apprehension in a noisy and dangerous Times Square video arcade. There, Vargas engages in the ultimate role-playing game, as she matches wits with a brilliant and deranged killer while time runs out for one of them.

This is by far the best in an already top-notch series whose expectations have been exceeded since the publication of MOST WANTED. Martinez continues to fine-tune her character both personally and professionally, walking a fine line between the familiar and the unexpected. COVER-UP is one more reason to add, and keep, Martinez on your must-read list.