The truth is that Jonni was hoping he could creep to his place in Class 3 without attracting anyone’s attention, so that Herr Knickel the strict teacher wouldn’t notice that he was late, but … he can hardly believe his eyes, surely this isn’t happening!
There are at least twelve dangerous-looking figures crouching on the teacher’s desk and on the window sills. The classroom has been invaded by pirates! They have a big fat book with them and it’s meant to contain information about where their ship has got to, as they seem to have lost it. But without a ship they can’t possibly retrieve the treasure that’s buried at the bottom of Inky Lake. Unfortunately, the only person here who can read properly is Herr Knickel – and the pirates have locked him up in the cupboard.
But, you can only discover how the pirates find their ship, how the teacher gets out of the cupboard and how Jonni and Class 3a eventually come across real pirates’ treasure if you read the whole book!