Peter Steffen

Pediatrician Waldemar Weber is at his wits' end. Of all days, his adopted son Egon—from his first marriage, whom Waldemar has always kept a secret from his young wife Henny—has announced he’s coming to visit on their first wedding anniversary. Waldemar must stop Egon at all costs. When Egon finally shows up at the door, he turns out to be a monkey trainer.

New teacher Heider takes up his post with great enthusiasm. His unconventional ideas meet with incomprehension and mistrust from the old head teacher Ruppert. When a boy has an accident on a school trip, the children blame Heider. The parents turn against him and he is suspended from his job. But Ruppert has come to respect the new boy. He does not believe he is to blame. Meanwhile, the children are preparing the next mischief. They want to blow up a ruin with explosives found in the forest. Heider is able to prevent this at the last minute. He is rehabilitated and everyone happily awaits his return to school.