Guardians of Time

There were six so-called Guardians of Time, who embodied different aspects of the universe and were thus masters of all of reality, perhaps even responsible for part of its creation.
Doc and Romana blow up and/or rescue a Space Princess from a Darth-Vader-wannabe on their hunt for the final Horcrux
The Doctor and Romana (I) are tasked by Colonel Sanders to find six horcruxes in this opener to the season-long ‘Key To Time’ arc
The Doctor is turned invisible, inaudible and intangible, and Steve and Dodo clown around in this both childish and completely racist serial.