Millie Bonnie Brown Bongiovi (born 19 February 2004) is a British actress and producer. She gained recognition for playing Eleven in the Netflix science fiction series Stranger Things (2016–present), for which she received nominations for two Primetime Emmy Awards. Brown has starred in the adventure film Godzilla: King of the Monsters (2019) and its sequel Godzilla vs. Kong (2021). She also starred in and produced the Netflix mystery film Enola Holmes (2020) and its 2022 sequel.

In 2018, Brown was featured in the Time 100 list of the world's most influential people, and was appointed as a UNICEF Goodwill Ambassador, the then youngest person selected for this position.