‘What’s what?’The last (so far) Bernice Summerfield novel, published in 2014, this is apparently tied into an audio box set that I haven't yet heard. I didn't mind. It's set on a spaceship called the Adorable Illusion, with Benny disguised as a disgraced fellow-archaeologist for Reasons and a motley assortment of crew and other passengers regarding her with more or less justified suspicion. Then about two thirds of the way through the book, there is a massive plot twist, and it turns out that we do actually care about everyone on board - very nicely done, as you would hope for from Russell who is one of the best Who writers when on form. I think you'd need basic familiarity with the Bernice universe to really appreciate it, though. You can get it here.
Next (and penultimate) in the set of Bernice Summerfield books is True Stories, edited by Xanna Eve Chown.