Children end up in Ancient Greece, where they learn the laws of physics from Archimedes.
| Actor | Role |
|---|---|
 Mariya VinogradovaKolya (voice) | Kolya (voice) |
 Olga GromovaOlya (voice) | Olya (voice) |
 Aleksei GribovArchimedes (voice) | Archimedes (voice) |
 Yevgeni VesnikGreek army commander (voice) | Greek army commander (voice) |
 Tamara DmitrievaLyre boy (voice) | Lyre boy (voice) |
 Anatoliy PapanovRoman centurion (voice) | Roman centurion (voice) |
| YYury AndreevGreek warriors (voice) | Greek warriors (voice) |
 Stepan BubnovMarcus Claudius Marcellus / Old greek warrior (voice, uncredited) | Marcus Claudius Marcellus / Old greek warrior (voice, uncredited) |