The first part of 'The Trial of a Time Lord', which means you should be looking to ensure you have the rest (that's 'Mindwarp', 'Terror of the Vervoids' and 'The Ultimate Foe'). There is an overarching storyline that continues and develops between the four and the whole makes more sense together.The idea is simple: the Doctor is put on trial by his own people for the crime of interference. The first three parts are individual stories presented as evidence, with the overarching storyline finalised in the fourth part.
This one is a good start - the interaction between the trial and the evidence is fairly minimal, so the traditional-style adventure of the Doctor and Peri can be enjoyed. The story was originally written by Robert Holmes, one of Doctor Who's best scripters, and is in fact his last full story. It introduces Sabalom Glitz, an intergalactic purveyor of dodgy goods, and has a quite mysterious planet - it seems like Earth, but its in the wrong position. Exactly what is the truth is revealed in part in this book - more is to come later...
This book only scratches the surface of the real reasons behind the Doctor's trial - and there is more to it than initially meets the eye. And there is a big question - where is Peri? Why isn't she still with the Doctor? All the answers are still to come...
