On the Calculation of Volume is a seven-book series by Danish writer Solvej Balle. It follows Tara Selter, a middle-aged woman who lives in a town just outside Paris. She runs an antiquarian book business with her husband, Thomas. What makes Tara special is that for the past four months she has relived the same day over and over. Every morning, she wakes up and finds that it is once again November 18th.

Balle first started work on the project in 1987, six years before the movie Groundhog Day came out and became shorthand for that particular form of time-loop story. The massive popularity of that film might have discouraged most of us, and Balle certainly did her best to abandon the idea, but it simply would not leave her. Instead, she has found herself in a time loop of her own, working on this series of novels for almost 40 years.

The first book of the series – published in Danish in 2020 and in English translation by Barbara J Haveland in 2024 – quickly built a fanbase and met critical acclaim. It was longlisted for the National Book Award for Translated Fiction in the US and shortlisted for the International Booker Prize; the first three volumes, taken together, have also won the prestigious Nordic Council Literature Prize. So far, six of the seven volumes have been published in Danish; Balle is working on the concluding volume. Book Three (translated by Sophia Hersi Smith and Jennifer Russell) has just been released in English.

Given how much time has passed, I wonder whether she can even remember how it all started.

“My very first book