Young adult novelist McConaghy (the Chronicles of Kaya series) makes her adult debut with the clunky chronicle of Franny Stone, a troubled woman who follows a flock of endangered Arctic terns on what is believed to be their final migration home. Franny’s mother, who vanished when Franny was seven, warned her that women in their family are unable to resist the urge to wander. While working at a university in Galway, she meets ornithologist Niall Lynch, who immediately declares they’ll spend their lives together, and they implausibly marry. Unfortunately, Franny’s overwhelming desire to travel, her sorrow over their stillborn daughter, and a sleepwalking episode in which she chokes Niall drive a wedge in their marriage. Niall had always longed to track the terns, and Franny does so by convincing a fishing boat captain that she can help him find fish in exchange for transportation. Despite the ragtag crew’s initial distrust of Franny, she becomes part of the team. McConaghy divulges more about Franny’s dark past as she writes Niall letters and reflects on their relationship, as well as the true nature of her quest. While McConaghy’s plot is engaging, her writing can be a heavy-handed distraction (“out flies my soul, sucked through my pores”). Lovers of ornithology and intense drama will find what they need in this uneven tale