Agnieszka Stelmaszyk (Polish: [aɡˈɲɛʂ.ka stɛlˈma.ʂɘ̟k]; born 6 January 1976) is a Polish writer of children's literature and young adult fiction. She is best known for her adventure young adult novels series Kroniki Archeo (2010–2020). Her other popular book series include: yough spy fiction trilogy Koalicja Szpiegów (2013–2014), children's mystery fiction Biuro śledcze. Tomuś Orkiszek i partnerzy (2014–2016), children's and young adult adventure trilogy Terra Incognita (2014–2015) co-created with Łukasz Ryłko, children's detective fiction series Klub Poszukiwaczy Przygód (2014–2019), children's adventure series Odyseusze (2016–2017), Imaginarium (2017–2018), Przypadki kociej gromadki (2018–2020), and Mazurscy w podróży (2019–2026), young adult mystery series Klub Przyrodnika (2021–2026), and children's detective series Alfred Wiewiór (2022–2023).
Agnieszka Stelmaszyk was born 6 January 1976. She has a university degree in Polish studies.
Her debut book, Opowiadania z morałem, a collection of short children's stories, was published in 2007. In the following years she also published children's books Mali Agenci. Dziecięcy świat przygód (2007), Niezwykłe święta Kornelii (2009), and Hinkul na bezkociej wyspie (2009). In 2009, her series of twelve children books titled Już czytam, were also published. In 2010, Tajemnica Klejnotu Nefertiti was published, being the first book in her most popular adventure young adult novels series Kroniki Archeo, which had 15 entries in total, the last being released in 2020.
Her other popular book series include: yough spy fiction trilogy Koalicja Szpiegów (2013–2014), children's mystery fiction Biuro śledcze. Tomuś Orkiszek i partnerzy (2014–2016), children's and young adult adventure trilogy Terra Incognita (2014–2015) co-created with Łukasz Ryłko, children's detective fiction series Klub Poszukiwaczy Przygód (2014–2019), children's adventure series Odyseusze (2016–2017), Imaginarium (2017–2018), Przypadki kociej gromadki (2018–2020), and Mazurscy w podróży (2019–2026), young adult mystery series Klub Przyrodnika (2021–2026), and children's detective series Alfred Wiewiór (2022–2023).
Stelmaszyk has a husband and a son. She lives in Bydgoszcz, Poland.
Biuro śledcze. Tomuś Orkiszek i partnerzy