That's right. Whoa.
Alistair Reynolds has written a Dr Who novel, and it's set in the Pertwee era, with Brigadier Lethbridge Stewart and Jo Grant and the Beardy Master. Deets at iO9, including spoilers.
"...he clearly has a lot of affection for the "UNIT family" era. But at the same time, Reynolds can't resist making things more intense and cosmic, and he winds up delving into some of the weirder contradictions of the UNIT era, including the sense that reality is always just a few threads away from unraveling, that runs underneath all the comfy "trundling around the English countryside in a yellow roadster" stuff in that era...
Reynolds is clearly having a lot of fun getting to play around with the Doctor Who universe, and he tosses out more ideas than he quite knows what to do with, somehow making the whole thing come together at the end. He's not just revamping the Pertwee era, he's making some interesting customizations to the show's mythology in general — particularly a lot of stuff about the Time Lords, and by extension the Doctor's own origins and ideals.
Reynolds brings out a lot of the weirdness that's inherent in a paramilitary organization coping with mind-bending terrors from outer space, and a lot of the threat that UNIT is dealing with this time around turns out to be existential in nature. On the TV show, UNIT soldiers deal with being frozen in time bubbles, de-aged into babies, mind-controlled by evil computers and whisked away to an antimatter universe — but Reynolds comes up with a possibly more surreal and jarring danger for UNIT to struggle against, as a result of the Master's evil-doing."
As much as I struggled thru a few passages of Chasm City, I'll be making my way from this place directly to Audible to see if there's an audiobook. And if not, an ebook.