Locking the Hypergreen, she made her way up the concrete stairs to the top floor. She knocked loudly on a door painted a monstrous shade of bright pink. After a few moments there was a muffled curse and the sound of movement from inside. The door opened and an attractive blonde in a very short bathrobe appeared, squinting blearily in the early morning light.Sophie Aldred is not the first Doctor Who actor to have written books in the continuity - both Bakers have turned their hand to it, as did Ian Marter back in the day and John Barrowman more recently. Noel "Mickey Smith" Clarke actually wrote a TV episode of Torchwood. She gives Steve Cole and Mike Tucker credit for assisting with the writing process here.
It's a story of Ace meeting up with the Thirteenth Doctor (and Ryan, Yaz, and Graham) in the present day, though a present day where Ace's ex-boyfriend is in charge of a rather small British manned space programme. Although there are some implausibilities in the set-up, I totally forgive this for a satisfying exploration of how Ace feels about the Doctor leaving her to it for decades. The alien threat, which I guess is meant to be the mainplot, is kidnapping young folks from London and the two protagonists get to grips with it. Ryan, Yaz, and Graham don't get a lot to do, but that's not the point. Plenty of continuity references, but also I think not too many to put off the non-Whovian reader. You can get it here.