Lately, the Ravens are acting funny: they are so fat they can't even fly. It seems like somebody has been feeding them - but who? Oto, Vik and Mai decide to investigate this mystery helped by Yoko, who makes them look like real detectives. After questioning some suspects and witnesses and examining some clues, they discover the culprit was Oto. The Ravens were eating the popcorn he couldn't finish - every single day.