Lucy, 23, pulled her hair up in to a bun and added some sunglasses before taking this revealing picture.
Posing in the New York apartment where she and the rest of the C4's Made In Chelsea gang are currently filming, Lucy's incredibly trim figure is clear to see.
It's not the first time Ms Watson has posted a picture of herself with very little on.
And it looks like Lucy's love of an under-dressed selfie could be catching.
On Monday, fellow MIC-er Jamie Laing shared a picture of his bestie Spencer Matthews wearing very little in NY.
We kind of don't know where to look in this snap...
What with half of the cast stripping off already, we are super excited to see what Made In Chelsea: New York brings to our TVs when it airs this summer!
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