Royal tutor Heine has been tasked with grooming four princes into potential kings. He’s interviewed the proud Prince Leonhard, but three more princes await: the highly intelligent Bruno, freewheeling Licht, and perpetually-glaring Kai. With each prince's personality as unique as the last, interviewing them will prove to be anything but straightforward...

Heine has finished interviewing all four princes and is ready to begin his first lesson, but will his young charges all assemble for it? And how did they do on their tests?!

Today's lesson: an incognito field trip into the royal capital! The sheltered princes are excited right out of the gate, but it looks like they might be scheming something behind their tiny teacher's back...

When King Viktor--also known as the war hero king--returns to the palace after a long time away, he summons Heine and the princes for an audience. But he isn't quite what one might imagine from his nickname... and he has some choice words for his tutor-spurning sons, especially Leonhard! With his claim to the throne on the line, can Leonhard get through the trial his father puts before him?

When he was a sickly child, Licht was always waiting in his bed for a certain person to visit... While strolling about the city one day, Heine steps inside a charming cafe--and the waiter who greets him is Prince Licht's spitting image! Is Licht's secret still safe, or is he in big trouble with the king?

From a young age, Prince Bruno has poured his utmost efforts into his studies to catch up with the crown prince who everyone saw as a genius. So when little brother Leonhard shows signs of genius, too--however unbelievable that may be--he panics. Can Heine help the brainiac prince decide what he really wants out of life?

Ever since the king pointed out Prince Kai's communication problems, the second prince has been confused about how exactly to go about improving them. Professor Heine and the prince's brothers have some advice for him, but can Kai muster the courage to put it into practice?

One year ago, Prince Kai was suspended from military school for violent misconduct. Now the incident is back to haunt him in the form of a tabloid article. Can Kai overcome his past by truly confronting it?

Little by little, the problem princes have been facing their flaws and learning more about themselves as Professor Heine grooms them for the throne. But when Count Rosenberg makes another appearance, they realize there's one thing they still know nothing about: the royal tutor himself...

Professor Heine sends the princes on an assignment to investigate rumors of a criminal in the palace, and the truth shocks them.

Heine has resigned from the post of royal tutor, and the search for his replacement is underway. Can the princes prove that they’ve matured under his tutelage?