In a certain green garden, behind a big old pear tree, stood a colourful little house. The scent of fresh tomatoes, basil and... cucumbers mingled there. Basia and Franek played a variety of games there every day. But one morning, just after breakfast, they woke up and felt that something was different. A spherical cucumber with a painted face rolled into the kitchen through the window! Behind him rolled the cucumber team, every vegetable laughing at full throat. - Basia! Do you see what I see? - asked Franek, rubbing his eyes. - I think I do... the cucumbers are laughing! - squealed Basia, grabbing her teddy bear. The cucumbers curled up like balls and cried out: - Cucumber, cucumber, laughter brings us together in a castle! Suddenly the garden soil trembled and a strange castle was formed from the combined cucumbers. It had cucumber towers, laughing windows and green doors. Smiling spider-like robots jumped out of the castle. Instead of thread, they had coiled cucumber whiskers! One of the robots introduced itself: - I am Cucumber Spider! And this is my friend Laughing Cucumber. Laughingtron started flipping goats across the cucumber bridge and giggling loudly. In a moment, the children noticed that everything in the garden started laughing - the watering can, the rakes, even the pebbles in the alley. Then Basia whispered to Frank: - What if it all leads to something... very unusual? Frank was already about to answer something when a fantastic green light flashed in the cucumber castle and the door slowly began to open....