Gyro Gearloose
While Scrooge McDuck is having a dream, the Beagle Boys invade his dream, via a device stolen from Gyro Gearloose, in order to steal the combination to his money bin. Since it is extremely difficult for a dreamer to stop themselves from correctly answering questions posed to them in dreams (according to the in-story dream science), Donald Duck must enter his uncle Scrooge's dream to prevent Uncle Scrooge from blabbing the combination to the Beagle Boys.