As more pictures emerge of Bridget Jones star Renee looking unrecognisable, she's not alone when it comes to making us look twice in shock
When we saw Renee Zellweger looking all kinds of different on the red carpet last week, we thought she was pretty unbeatable when it came to shocking us.
And now she's been spotted again without make-up looking just the same, we were sure of it.
But just hours later, photos of celebrity chef Heston Blumenthal have emerged, and he looks like a totally different person too.
How do they do it?
But they're not the only stars to transform before our eyes - and some are completely unrecognisable.
From both Kris and Bruce Jenner to Tulisa and Nicole Kidman, we've seen some huge changes and they're all in good company as Hollywood experiment with their appearances.
Pull these slider images across to reveal the stars before and after their transformations:
Kris Jenner has spent a fair few years propelling her whole family to stardom, and we've seen the momager change in the process.
While the brunette beauty has kept her youthful glow, her face appears different to how it did back in the 90s.
Kim's mum has had a face lift and is also rumoured to have had a boob job to stay looking young at 58-years-old, and hasn't exactly hidden her love of cosmetic surgery.
When she welcomed the late chat show host Joan Rivers on to her show, Kris even agreed 'everybody looks better with plastic surgery' on air.
And she openly admitted having the face lift ahead of Kim's wedding to Kris Humphries in 2011, telling Australian Radio: "I did have a little freshening up."
She added: "Kim thought my chin was down to my waist. So I had a little lower... they take your chin and pull it up."
They're not the only ones though - check out our gallery of changing faces
