Pluto's taken a hit over the past few years, with certain scientists casting nasty aspersions about the state of its planethood, but back in the 1970s when The Sunmakers was made, it was going strong. There are several megropolises on the planet, with Megropolis One serving as the administrative center. Megropolis One is the location of one of Bob Holmes' most overtly political Doctor Who stories. Subtlety does not factor into The Sun Makers. It's a land ruled over by an entity known simply as "The Company", which exploits its workers and drugs them with a chemical called PCM, making them subservient. They're all taxed extensively, and the inability to pay taxes is considered a capital offense. There is a seedy under city filled with people who have broken away from the Company, and are plotting a revolution to overthrow them. The Doctor, of course, helps them in their efforts. But a story about the after effects of the revolution, or even one depicting how the Company came into power, would be interesting enough to fill an entire series, let alone a couple episodes. So let's show some solidarity with Pluto and bring back Megropolis One!