The earthlings discovered other nearby planets with anti-Ming factions .
The earthlings put together a loose coalition , determined to overthrow Mongo 's evil emperor and return Princess Thundar , Flash , Dale , and Zarkov to their native planet .
The earthlings discovered other nearby planets with anti-Ming factions and put together a loose coalition , determined to overthrow Mongo 's evil emperor and return Princess Thundar , Flash , Dale , and Zarkov to their native planet .