The second sentence of the gripping “Whistle in the Dark” reveals that a teenager who disappeared has been returned safely to her family. So, right away, novelist Emma Healey announces that “Whistle” won’t be the book we might expect.

That’s a good thing, too, since there are plenty of thrillers about families searching for a missing child (in YA, it’s practically a subgenre). Even the already-returned territory is not new — Bret Anthony Johnston’s 2014 “Remember Me Like This” insightfully explores what it might be like for a family to recalibrate itself after a missing teenager returns — but Healey makes “Whistle” fresh and surprising by connecting Lana’s recovery from the trauma of her disappearance to the painful reckoning of her mother, Jen, who is equally lost.

Even before she vanished, Lana was depressed and suicidal, so her parents are alarmed when she returns and is unwilling or unable to say where she had been for several days. Jen, in particular, is weirdly focused on figuring out what happened: Aliens? The occult? The hunky boy down the lane?

Her amateur detective work pays off eventually, but the search takes her down a paranoid path that isolates her from her family and endangers her life.

Fans of Celeste Ng or of Healey’s observant debut, “Elizabeth Is Missing,” in which an elderly woman with dementia keeps insisting that something sinister has happened to her absent friend, will recognize the new novel’s DNA. Like her first book, “Whistle” is a hybrid of psychological thriller and domestic drama with a protagonist whose viewpoint is unreliable and a set of mothers and daughters whose relationships feel complicated and real.

Healey is especially sharp on the specifics of the bond between Lana and Jen, with Lana alternately remote and sarcastic and Jen eagerly reading the tea leaves of Lana’s behavior for signs their strained relationship is improving. Jen also seems to suffer from depression. As she spirals into relentlessly spying on Lana, “Whistle in the Dark” becomes a creepy meditation on how out of control it can feel to be a parent of a teenager, as when Jen feels “a sudden exhaustion from the burden” of her love for her daughter:

“Why did she have to drag this love around everywhere when, sometimes, she’d like to leave it behind for a few hours?”

Jen’s relationships with her elder daughter and her own mother get less page time in “Whistle,” but they are equally credible. In fact, the only underdrawn character is Jen’s husband/Lana’s dad. He does have a name, but it’s barely worth recalling, since he’s like one of those blandly amiable dudes who doesn’t get the girl in a rom-com: His chief role is to stand on the sidelines and agree with everyone.

For the record, he’s Hugh and he’s so much less compelling than Healey’s female characters that you almost wish he’d disappear.

 

Whistle in the Dark
By: Emma Healey.
Publisher: Harper, 330 pages, $27.99.