"What the Dead Know" by Laura Lippman; William Morrow, $24.95

Laura Lippman's latest crime novel, "What the Dead Know," heralds a leap forward in her fiction, from very good to great.

Lippman got on the national radar 10 years ago with her series starring Tess Monaghan, a disgruntled ex-newspaper reporter turned amateur sleuth. But Lippman always had a streak of poetic melancholy in her writing that gave the mystery series a gravitas.

It's from that gravitas that "What the Dead Know" stems. The novel is not in the Monaghan series.

The book begins with a hit-and-run accident near Baltimore. When the police catch up with the fleeing driver, they discover a middle-aged woman who seems both utterly confused and completely cagey. For one, she won't tell them who she is — except to hint that she might be one of "the Bethany girls," two teenage sisters who disappeared 30 years earlier.

Then she clams up. The rest of the book is an attempt by a police detective to figure out who this manipulative blonde might be; and what makes the book so exhilarating, what marks Lippman's leap upward as a writer is that the reader is just as involved in the mystery as the characters.

Lippman structures "What the Dead Know" with passages in the present and in the past, and with chapters devoted to the Bethany parents' histories as well as the girls'. She never loses the pitch of any of these interlocking characters, or restraint and insight.