Asterix and the Big Fight

When Getafix becomes an amnesiac lunatic after being struck by Obelix's menhir, Asterix tries to cure him, all while his fellow villagers are being conned by a phony soothsayer. When the druid Getafix is attacked by some roman soldiers, Obelix drives them away by throwing a menhir on them - which accidentally hits Getafix. After this the druid has lost his memory and can not remember the formula of his magic potions, especially the one which gives superhuman strength. —Michael Zink