Holly and her friends look with eyes full of bewilderment at a nondescript piece of blue paper with some incomprehensible numbers. So this is what, it turns out, was in that mysterious wallet, which, in front of the guys’ eyes, a strange stranger threw on the roof of a bus stop, and then rushed away as if scalded! But what is this leaf that the suspicious guy needed to get rid of so quickly? Ticket? But where? Ticket? But for what? Or maybe... “Maybe stop guessing?” - the young detectives tell themselves and begin a new investigation. And the most ordinary shoes will help them with this...