Original script by Douglas Adams, novelization by Gareth Roberts.
The Doctor (4th incarnation), with Romana and K-9 in tow, returns to England in response to an urgent message from an old friend, an elderly Time Lord living in quiet retirement as a Cambridge professor. It turns out Professor Chronotis brought some things with him from Gallifrey that he technically isn't supposed to have, and one book in particular has the potential to be appallingly dangerous...and that book was among a handful borrowed by a grad student who means to use it to impress a girl.
It seems my theme for my week off was humorous science fiction. Where Redshirts obliquely evokes Star Trek, this is a direct tie-in with Doctor Who, but it's the Doctor Who of the 1970s, not the current version. I may as well admit up front that Tom Baker was, is, and always will be my Doctor. When I was in high school the local PBS affiliate ran a half-hour episode of the show every weekday at 6:30, and it was the Tom Baker stories that were airing when I first tuned in.
But the first Doctor Who story I ever saw was actually "The Five Doctors," which used footage from the unfinished "Shada" to shoehorn Tom Baker into the story when the actor declined (or was unable, I forget) to return for the anniversary special. So the Doctor's first appearance in this book was remarkably familiar to me!
About the same time I was memorizing the names of the Doctor's companions in order from 1963 to the present, I was also discovering The Hitchhiker's Guide to the Galaxy, both the books and the radio series, and memorizing those through pure repeated exposure. I have not brought myself to read And Another Thing, the sixth Hitchhiker book by Eoin Colfer, but I couldn't pass up a new old Doctor Who story. And I think Gareth Roberts did a pretty good job of capturing Douglas Adams' tone; it's a very funny book. My boyfriend, who loves Douglas Adams but has never watched Doctor Who, also approved.