This is the 3rd Doctor final story and I think it's a good one. A sort of sequel to The Green Death, this story see alien spider's trying to get back a blue crystal that the 3rd Doctor took from them the last time he came to their Planet.
This story is the first time the term Regeneration is used in Doctor Who, the last apperence of the Who Mobile and the first apperence of the 4th Doctor played by Tom Baker.
The late great Jon Pertwee's final story. It's more of a whimper than a bang for his exit.
The story itself isn't bad but the fact that one car chase lasts over an entire episode does make a little hard going in places.
Saying that, the team are great, Pertwee, Liz Sladen, Nick Courtney et al put in some fine performances.
I'm looking forward to the 90 minute edit, should make the story much more exciting.