Just because we were talking about a possible cross-over, this is the latest one we did! What do you think? Do you know the reason of Perty’s last line?
Well, basically at the beginning of the 3rd Doctor’s era, the TARDIS wasn’t able to travel trough time (becuase of the ban of the Time Lords) also, the Doctor was a totally car geek and he used to travel with his beloved Bessie.