The slender, alarmingly beautiful woman in the Heathrow lounge sweeps her long red hair away from her face, crossing and uncrossing her legs as she sips her martini. Her name is Lily, and she’s reading Patricia Highsmith. That’s a sure sign of trouble, especially for Ted, the corporate-takeover artist who shares a first-class aisle with her and half-drunkenly confesses his desire to kill his unfaithful wife. Lily’s reply: “I think you should.” That simple recommendation sets in motion a swirly, slippery series of events—Strangers on a Plane, you could call it—as Lily agrees to help Ted and reveals a backstory that proves she’s more than qualified for the job.
That’s only the first two chapters. As the thriller slinks smoothly along, Swanson (The Girl With a Clock for a Heart) divides the action among four narrators, each one of whom, even the dweeby detective, is repressing a maelstrom of secrets. The sole character who engenders sympathy is a lummox house builder, just far enough past his glory days that he falls under the sinister spell of not one but two femmes fatales. Swanson isn’t skilled at distinguishing between the voices—Lily and Ted’s wife speak in the same elevated minx tone—but he has a tight, assured grasp on the macabre. Swanson returns several times to an old moss-covered well behind a Connecticut farm, a tranquil site lush with wickedness. A concealed EpiPen makes for a throat-grabbing killing tool. And he slips a malicious zigzag into the book’s very last paragraph, a twist that exposes the nerve we all have to be seduced by a murderess. B+