Related Clues:

• Rare and wonderful
• Nonnative
• From another planet
• One with a big head?
• Out of this world?
• UFO occupant
• Worf or Troi, e.g.
• Weaver's work
• Ufologist's study
• UFO passenger
• Klingon, e.g.
• Sci-fi villain
• Unheard-of
• Noncitizen
• 42-Across, for one