They're married to other people. But tonight, after six years of casual sex, a couple is trapped in a hotel room. As a fire rages below them, they are forced to confront the lies they've told their spouses, each other—and themselves—in this edge-of-your-seat, witty, sharply observed novel.

Nick Holloway is forty-six. He is the picture of success: a successful partner at a law firm, with a gorgeous wife, a precious daughter, and a house in the suburbs. If he also has gnawing disappointments, secret yearnings, and a creeping sense of opportunities wasted, well, that’s nobody’s fault but his own.

Jenny Parrish is forty years old. She has two lovely sons, a devoted if somewhat hapless husband, and recently has gained success as a wildly popular young adult author. It’s a dream come true, a perfect life! So perfect, she can’t help but wonder sometimes whether it’s all going to come crashing down.

If Nick and Jenny run into each other in town, they politely acknowledge each other the way slight acquaintances do: a brief nod, a small hello. However, these two are much more than slightly acquainted. For the past six years, they’ve been meeting at least once a month and having sex. Lots of sex. Great sex. They do not discuss their spouses, they never spend the night, and they never ever talk about what their relationship means. Because this thing they have? It’s casual. Uncomplicated.

When Nick books a night at a fancy new hotel in Manhattan, the two decide to break one of their rules and spend the whole night together. It’s business as usual—until a fire alarm goes off. At first they think it’s a false alarm, but by the time they decide to leave, it’s too late. As the fire climbs, the heat rises not just outside their room but inside as well. Emotions run hot as fear strips away their defenses and justifications, forcing Jenny and Nick to be honest, with each other and with themselves, about how they ended up in this room, and what these six years have really meant.

Eliza Kennedy has written a novel that masterfully explores marriage, infidelity, and love. A meditation on whether it’s possible to live an authentic life, and whether we can ever show our true selves, it is a literary triumph.