- Original title: Sirli, Siim and the Secrets
- Illustrator: Agnieszka Cieślikowska
- Translator: Marta Perlikiewicz
- Language: Polish
- Widnokrąg
- 2026, 240 pp
- ISBN: 9788368060379
- fiction, fantasy, storybook
- Age: 6+
Tajemnicze światy Sirli i Siima
