Finally, the holidays are here. Vlad and his friends are so excited. Jérôme, Vlad's father, is in charge. André, the grandfather of Jeanne and Basile, is also here to help. Six kids, two adults, an eight-hour train trip. Nothing could go wrong. But Jérôme and André miss the train... and watch it leave the station with the kids on board. It's the beginning of a crazy race for the unlikely duo. While the unsupervised children go wild and have the time of their life, André and Jérôme go through various delays and adventures.