The Doctor's old school pal Drax gets him and Romana in quite a bit...
The Doctor's robotic dog got his own show.
The Doctor, Rose, and Mickey investigate a school with help from another former companion.
The Doctor checks into an adventure he doesn't quite remember with a pair of...
The Fourth Doctor. "Warriors' Gate,"Final Episode.
The Fourth Doctor. "Destiny of the Daleks," Episode One.
The Fourth Doctor. "The Power of Kroll," Episode One.