A review by robinlikesreading
Doctor Who: The Third Doctor: The Heralds of Destruction by Paul Cornell

4.0

I've never seen any of the third Doctor's episodes (yet) so I guess this was my first third Doctor story?
Anyway, it's fun. It takes place after the Doctor's exile ended and he's allowed to leave planet earth again. The earth gets attacked by an 'alien invasion' and The Doctor works together with Unit and even with The Master to stop this invasion.