There are two sides to every love story. Even supernatural ones. This is the companion novel to David Levithan's unforgettable bestseller Every Day. Every day is the same for Rhiannon. She has convinced herself that she deserves her distant, moody boyfriend, Justin.

She knows the rules: Don't be needy. Avoid upsetting him. Never get your hopes up. Then, out of the blue, they share a perfect day together - perfect, that is, until Justin doesn't remember anything about it.

Confused, and yearning for another day as great as that one, Rhiannon starts to question everything. And that's when a stranger tells her that the Justin she spent that time with & wasn't Justin at all. Levithan's powerful novel explores the complexities of first love in a unique way that will captivate anybody who loved Rainbow Rowell's Eleanor & Park and Jandy Nelson's I'll Give You the Sun. David Levithan is the new York Times best-selling author of Boy Meets Boy and Marly's Ghost.

He is also co-author with John Green of Will Grayson, Will Grayson. and with Rachel Cohn of Nick & Norah's Infinite Playlist.

David's latest collaboration with Rachel, The Twelve Days of Dash and Lily, was picked by Zoella for her Book Club with WHSmiths.

David is also a highly respected children's book editor, whose list includes many luminaries of children's literature, including Garth Nix, Libba Bray and Suzanne Collins.

He lives and works in New York.