Gideon the Ninth by Tamsyn Muir (Tor, 2019)

★★★☆☆

“Lesbian necromancers explore a haunted gothic palace in space! Decadent nobles vie to serve the deathless emperor! Skeletons!” —Charles Stross

What it says on the tin?

Except that “exploring” doesn’t start until around the 40% mark. The first third of the book is spent on “vying”: if that’s what we can call sitting with the characters while they niggle each other and otherwise don’t do very much.