Who's Who? - S1.E60

During 'Operation Catapault,' Dastardly falls out of the plane and lands on his head. As a result of this, he loses his memory. Klunk takes command of the squadron, but their operations are no more successful than before. Eventually, Dastardly, Zilly and Klunk all fall on their heads from a plane. Dastardly's memory is restored by this, but now Klunk and Zilly don't seem to know who he is or who they are...