The Third Doctor deals with the Master and a foe of a previous incarnation.
Sergeant Benton
The Ninth Doctor, Rose, and Captain Jack help out the Brigadier in the 70s...or...
The Fourth Doctor. "The Android Invasion," Final Episode.
The Fourth Doctor. "The Android Invasion," Episode Two.
The Fourth Doctor. "Terror of the Zygons," Episode Two.
The Fourth Doctor. "Terror of the Zygons," Episode One.
The Fourth Doctor. "Robot," Final Episode.
The Fourth Doctor. "Robot," Episode Three.
The Third Doctor. "Planet of the Spiders," Episode Two.
The Third Doctor. "Planet of the Spiders," Episode One.
