Following a fall during mistletoe picking, Druid Getafix decides that it is time to secure the future of the village. Accompanied by Asterix and Obelix, he undertakes to travel the Gallic world in search of a talented young druid to transmit the Secret of the Magic Potion.
Johan, a talented pianist who lacks confidence, prepares for a major musical competition. Overcome by stress, he takes refuge in the women's toilets where he encounters a young woman who provides him with a different destiny.
