The Song of Achilles
by Madline Miller

This one really tailed off half-way through. I found the characters very one-dimensional (Patrcolus pines after Achilles, Achilles has muscles and can swing a sword fast), but the story took me at least up until the half-way mark. Weirdly I wasn't interested too much when the actual Iliad story line started to get going - maybe because I've heard it a million times before - and their essentially non-existent romance (more accurately an inch-deep obsession, I'd argue) didn't exactly inspire me to carry on reading.