Voir Professor Balthazar, Season 2 - Episode 6

Inhabitants of Balthazar-City have troubles with frogs since their croaking prevents them from sleeping. Professor Balthazar redresses this trouble ingeniously - and even more: among tedious frogs, Professor Balthazar discovers musical frog, Figaro, a real virtuoso in whistling opera arias. And so Balthazar-City becomes a famous musical center.