A 'lost adventure' of Doctor Who scripted by Douglas Adams, beloved author of The Hitchhiker's Guide to the Galaxy, novelized at last with the approval of the Adams estate. The Doctor's old friend and fellow Time Lord Professor Chronotis has retired to Cambridge University where no one will notice if he lives for centuries. When he left Gallifrey he took with him a few little souvenirs. Most of them are harmless. But one of them is extremely dangerous. The Worshipful and Ancient Law of Gallifrey isn't a book for Time Tots. It must not be allowed to fall into the wrong hands. And the sinister Skagra most definitely has the wrong hands. He wants the book. He wants to discover the truth behind Shada. And he wants the Doctor's mind!