Edge Of Destruction
Is The Edge Of Destruction the only Classic Who story that takes place entirely within the TARDIS?
shareYes. A significant part of Castrovalva's first two episodes also takes place exclusively in the TARDIS (and has a similar storyline) but they do come out eventually. A lot of Invasion of Time also takes place in the TARDIS too, but again, nowhere near the whole story.
So this is permanence, love's shattered pride.
What once was innocence, turned on its side.