Earth - a small, insignificant planet. Entirely devoid of intelligent life.
At least that's according to the legal documents. The Doctor, Romana
and K9 find themselves at the centre of a most unusual trial.
An intergalactic corporation wants to bulldoze the planet for a
development project. Only a previous court's preservation document is
standing in their way. The Doctor has been summoned as an expert
witness. If he can prove Earth contains intelligent life, the whole
world will be saved.
But with a fortune at stake, it was never going to be that simple.