I think one of my fellow staffers hit the nail on the head when, just this morning, she gasped "What's been up with Rachel Bilson's style lately?!"

While I usually love the actress's preppy, yet casual, style, she's been throwing me for a loop lately with one-offs like this Preen dress (worn to the “Waiting for Forever” screening in New York).

You don't need X-ray vision to see what's under this dress.

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Photo: Joe Kohen/WireImage