Emma Watson has been hiding surprises for commuters on the London Underground - copies of her book club Our Shared Shelf's latest read.
The copies of Maya Angelou's Mom & Me & Mom will have messages from the actor in them, and some commuters have already found the books.
Ms Watson left the books down the sides of the escalators.
It seemed no one recognised her in the video she posted, and one user commented: "The sad thing is, everyone in London is in such a rush to get places I'm sure no one even recognised her!"
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Some lucky commuters have already found the books.
Emma Watson created a feminist book club as part of her work with the UN.
On the Goodreads page for Our Shared Shelf, she wrote: "As part of my work with UN Women, I have started reading as many books and essays about equality as I can get my hands on.
"There is so much amazing stuff out there! Funny, inspiring, sad, thought-provoking, empowering! I've been discovering so much that, at times, I've felt like my head was about to explode... I decided to start a Feminist book club, as I want to share what I'm learning and hear your thoughts too.
"The plan is to select and read a book every month, then discuss the work during the month's last week (to give everyone time to read it!). I will post some questions/quotes to get things started, but I would love for this to grow into an open discussion with and between you all.
"Whenever possible I hope to have the author, or another prominent voice on the subject, join the conversation."