THE EDEN TEST, by Adam SternberghA woman surprises her husband with a weeklong couples’ retreat in “The Eden Test,” Adam Sternbergh’s new thriller. Threat shimmers around their isolated cabin, though one suspects that nothing would force them to endure anything more painful than a week of “working on the relationship.”On their first date, three years earlier, Daisy licked a smudge of crème brûlée off Craig’s chin, a mischievous gesture that bound them together. They spent weekends together eating croissants and reading the paper, “its sections unfurled all around them like blueprints for some brazen upcoming heist.” “The Eden Test” shows how a couple in love can seem like a two-person army, fugitives from the outside world. As the novel’s epigraph, from Adam Phillips, puts it, “A couple is a conspiracy in search of a crime.”Now, Daisy and Craig appear less like co-conspirators than adversaries. The denim overalls that Craig used to strip off Daisy have become “those [expletive] overalls she always wears.” And Daisy is cleareyed about Craig’s failings, from his infidelities to his pretension about restaurants, “as though he’d studied in the finest culinary schools of Europe, rather than being just another dude in Brooklyn with a credit card and a subscription to Bon Appétit.” Craig is preparing to leave her for his mistress, and Daisy hasn’t been entirely honest with him, either.

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