This passenger immediately seemed suspicious to the twins Vasya and Petya. Especially when I pushed my suitcase under the bench - and it... disappeared! A real invisible bag! Why does a pretty girl need him, what is she hiding from customs inspection? Guns, bombs, drugs? The boys set out to find out - after all, even their own father did not believe their suspicions. Meanwhile, the cunning villainess went wild: she threw her accomplice off the train, deciding that he had stolen her precious luggage. But in fact, Vaska and Petya hid the bag - and this became the first part of their daring plan...