London — Millie Bobby Brown, the teenage star of hit Netflix drama series "Stranger Things", is among a host of celebrities taking on the colour blue for a UNICEF film to mark World Children's Day.
The 14-year-old actor, the youngest person to make Time magazine's list of the world's 100 most influential figures, symbolically changes her last name from Brown to Blue - the colour of the UN children's agency - for the film.
"World Children's Day is a fun day with a serious message," said Brown in a statement on Thursday ahead of the global day of action to mark the adoption of the Convention of the Rights of the Child on Nov. 20, 1989.
"It is a day where all children are encouraged to speak out about what matters to them, like education, safe spaces to learn and play, and positive environments.
"By going blue for UNICEF on this day, we are demanding the world provide a brighter future for kids."
The British teenager has twice been nominated for an Emmy for her role in "Stranger Things", which followed the case of a missing boy named Will in a small Indiana town in the 1980s.
Brown, who plays a girl with special powers who tries to help rescue him, has spoken out in the past against bullying and last year deleted her Twitter account after a slew of hate-filled comments.
In 2016, at the age of 12, she co-hosted UNICEF's 70th anniversary celebrations in New York, interviewing David Beckham on stage.
The UNICEF film shows her rallying fellow celebrities including singer Dua Lipa and actors Liam Neeson and Orlando Bloom over the phone with the words "code blue".
Lilly Singh, the YouTuber who said this week she was taking a break from the video platform, is shown making "Blunicorn" smoothies, while Lipa replaces the word "red" with "blue" in her song "Be The One".
The Convention of the Rights of the Child has been ratified by 196 countries and includes a child's right to "know and be cared for by his or her parents" and the right to a name and nationality.
UNICEF is calling on people to sign an online petition asking for leaders to commit to fulfilling the rights of every child, and to wear something blue on World Children's Day.
- Reporting by Rachel Savage; Editing by Claire Cozens