While experimenting on the 999, the Ghost Hoppers put the three to a nearby jail. One of the Ghost Hoppers explained that they colonized Kilimanjaro two years ago, and eradicated the local aboriginal population. The artificial suns (which became the triple sun) they launched resulted in their two-dimensional appearance. The Ghost Hopper Queen's mothership appeared to halt the experimentation. She restored the 999 and released the three. The Queen, disgusted by the unethical pursuit of science by her own people, also left the Nebula. (thetvdb.com)