Jarlath “Jar” Costello, a London-based internet click-bait content writer and hero of J.S. Monroe’s thrilling debut, has started seeing a dead person. Specifically, he’s been seeing glimpses of Rosa Sandhoe, his girlfriend who leapt to her death into the sea off Norfolk in 2012 when she was a student at Cambridge University.

Five years later, Jar is certain of two things: that Rosa and he are soul mates and that she’s still very much alive. A body was never recovered. When he gets hold of an encrypted file containing Rosa’s journal, his faith is confirmed and his search for her kicks into high gear. A gear so high that the pages all but turn themselves as the story unfolds in taut chapters alternating between Rosa’s journal entries and Jar’s frantic quest.

Monroe adds more voices in the book’s second half, keeping the guess-who’s-crazy/guilty ball in the air until the all-consuming reveal. Pacing is crisp and the plot is credible, but it’s the cast of expertly crafted, psychologically ambiguous characters that rivets. Monroe is the pseudonym of a well-known British author and journalist.

J.S. Monroe. Mira, $26.99 (384p) ISBN 978-0-7783-3001-1

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