Mary Poppins: Did she really fall through a bath?!

If you've seen the new Mary Poppins Returns movie you might be wondering how they filmed some of it.

And one scene in particular might have got you thinking - the bit where they slip through a bath into an underwater world.

A lot of people thought it was probably CGI but it turns out it's real...well some of it.

Sadly the underwater world isn't, but Emily Blunt who plays Mary Poppins really did slide through a bath!

Don't believe us? Have a watch of this.