Rachel Weisz’s Mysterious Hair Day

Gray hair…it happens sooner or later!

But could that be why Academy Award winner Rachel Weisz braved the frosty New York City temperature and popped into a hair salon?

The 37-year-old Constant Gardener actress was snapped while walking into the beauty establishment. She wore a black North Face coat and white cap over hear head.

Once inside, the natural brunette was spotted in the window with hair dye on her roots.

Weisz, who is married to director Darren Aranofsky (The Wrestler), is getting ready to start shooting the Phillip Noyce film Dirt Music.

Rachel will appear in the flick opposite recent Golden Globe winner Colin Farrell and Russel Crowe.

Do you think the dye job was for Rachel’s role in the movie, or to cover up her pesky grays?