This review is from: Doctor Who: Matrix (Mass Market Paperback)
Challenged by a mysterious enemy the Doctor decides to Journey back to 1963 to leave Ace with his first incarnation. Instead they arrive in a London that bears little resemblance to what it should be and the Doctor seems never to have existed. The sense of doom and wrongness is reinforced by an encounter with Ian and Barbara who apparently never taught a Susan Foreman nor met the First Doctor as they should have.
The dark tone of the book is unrelenting as Ace ends up abandoned on the unforgiving streets of London in 1888. Much of the focus of the book centres on Ace as she tries to come to terms with being homeless and destitute in Victorian England with little hope of seeing the Tardis again. Ace's infection by the Cheetah People has been touched on before in the Virgin New Adventures but never explored to such a degree as it is here.
All the characterizations are well constructed and the plot is never predictable, without the reams of incomprehensible psycho/techno-babble that other writers seem to resort to.
Another excellent addition to the series by a writing partnership who know what they do best: Ace and the Seventh Doctor.