Kaoru, a friend from the piano class Ruli once attended, has gone missing. While searching for her, Ruli and the gang find a strange dent and her shoes. And as they continue their search, Hiro is suddenly asked a mysterious riddle.
Hiro's study files!
!ملفّات دراسة هيرو
Hiros Lernaufzeichnungen!
¡Los archivos de Hiro!
¡Los archivos de Hiro!
Les observations de Hiro !
sui 
Digimon
Познавательные уроки от Хиро!