At least in this one we get to see Sam as well as the Doctor. In fact much of this book is Sam; in her guise as ingenue bio-protester/eco-terrorist. A lot of this book is taken up with learning experiences for Sam, both in the field of who she can trust, and what "eco" means in a galaxy with non-human sentients. Unfortunately for her, while she interacts with the him, she doesn't get reunited with the Doctor.
I enjoyed this book, although it gets a bit confusing in places.