Willi has planted a seed that refuses to grow, no matter how hard he tries. His best friend Lina has an idea: he needs to travel to a wishing well in Rome. Willi sets off, finds the well, and learns how important true friends are. Willi has planted a seed for a banana plant. Now he waters it and waits and hopes, but nothing happens. Then Lina knocks on the door. She has the solution to the problem: he must go to Rome, where there is a well into which you throw a coin and make a wish. Willi packs a banana and his toothbrush into a small pink suitcase and takes the train. Lina prefers to stay home; someone has to water the seed. The journey is long and traveling makes you hungry, so Willi first eats a plate of spaghetti in Rome, even though he would have preferred a banana, fried or roasted. While searching for the well, he wanders through the city and even ends up in a museum. Finally, he finds the well and throws his coin in, but – nothing happens! However, when Willi arrives home, a big surprise awaits him.