Hannah is a new mom who wasn't sure about the idea of children for most of her life, but is absolutely enamored with her infant son, Jack. She's struggling post-partum, though, haunted by the image she swore she saw in the delivery room of Jack not making it. She's fixated on tending to Jack to keep it from becoming a reality, and is going to therapy to work through it. But husband, Adam, insists this anxious person isn't who Hannah is, and initiates a separation. I want to throttle him. 

Overwhelmed with emotions and exhaustion, Hannah wonders briefly what her life would have been like if the delivery room nightmare that haunts her had been real, and suddenly is transported to another reality. In this world, her and Adam are still together, but Jack doesn't exist. After freaking out and returning to her reality, Hannah chalks this up to a waking nightmare from sleep deprivation. Until later when Jack disappears into thin air, and people start forgetting he exists. 

After another 'waking nightmare' where she meets a version of Adam that knows she's not 'his Hannah', and seeing the same two strangers in multiple 'nightmares', Hannah is on a mission. Figure out if she just really needs a nap (relatable), or if she can really travel between realities, and how to find HER Jack and keep everyone where they belong.

The physics involved in this book were fascinating to me, and I loved that Hannah was a horror author. Sometimes reading books where the MC is a writer can be annoyingly meta, but this did not feel cheesy and was a fun lens for her to see things through. I definitely felt vicariously gaslit and stressed by the characters' disregard for Hannah's experiences, and the end got a little wonky for me, but this book had some really interesting and beautiful takes on emotions and love told in a way I've never read before. I think this would hit harder for moms, but I enjoyed it regardless.

Thank you to NetGalley, the publisher, & the author for the advance copy in exchange for my honest review.