Scooby-Doo and the Alien Invaders

The third direct-to-video film based on Scooby-Doo, released in 2000 and featuring aliens from outer space.

Tropes used in Scooby-Doo and the Alien Invaders include:
  • Aliens Are Bastards: The movie seemingly plays this straight, but it ultimately averts it. It turns out that the aliens that are evil are actually humans and that Crystal and Amber are aliens though they're actually good.
  • Cowardly Lion: A rare case where Shaggy and Scooby manage to shift from Lovable Coward into this Trope in order to help Crystal and Amber.
  • Distaff Counterpart: Though she's technically from outer space, it's noted that Crystal and Shaggy are a lot alike. The same applies to her dog Amber though she's technically an alien too though she's a more animalistic alien than Scooby. It turns out that like Scooby, she's capable of speech, though it's more coherent.
  • The Greys: Crystal's true appearance.
  • Humans Are the Real Monsters: The evil aliens turn out to actually be human. The actual aliens are rather innocent.
  • Innocent Aliens: Crystal and Amber both turn out to be this.
  • Scooby-Doo Hoax: As per series tradition, but in this case, the crooks are hindered by two real aliens.
  • Statuesque Stunner: Shaggy notes that during his love song about Crystal that she is rather tall. Technically, they're about the same height.