This is How You Lose the Time War, by Amal El-Mohtar and Max Gladstone

Red and Blue are on opposite sides in a war through all of time. They zip back and forth, to see London on fire after a plague, or being built by the Romans, or the Underground used by robots long after all the people are dead - and to places that aren't London or Earth. In between hostilities, Red and Blue correspond, their letters written secretly in obscure media, such as the sting of an insect. They taunt one another, they promise the other's defeat.

And they fall in love.

This rich, compelling novella won a bunch of awards, including a Hugo and BSFA. I'd been meaning to get to it for ages having heard good things. By chance, some last-minute work stuff has meant I'm dashing about this week and could listen to the audiobook on the way. I felt rather in synch with the dashing about of the plot.

Cynthia Farrell and Emily Woo Zeller are good readers, and provide suitable heft and gravitas for such an epic story. Even so, I suspect I might have preferred the experience in print, as several times I wanted to skip back to a previous letter or incident. There are interesting things going on with the way the protagonists are described, their pronouns, their very modes of being, which I may have absorbed better from the printed page. I followed and enjoyed it, but think I may have missed some of the richness.

That's certainly not a complaint. My first thought on finishing the book was that I wanted to read it again, to pick over the nuance and detail. How very time war to want to run events again and see if they are different.