Both ladies were snapped sporting the white silk frock by Willow, which retails at a staggering £1,175 (gulp!).
Mother-of-two Isla was the first to wear the white gown as she supported hubby Sacha Baron Cohen at the London premiere of Les Misérables in December.
The Great Gatsby actress let her statement dress do the talking by adding simple Louboutin heels, a delicate silver necklace, and super-sleek locks.
Now, we have spotted Sheryl Crow sporting the exact same frock at the 2013 CMT Music Awards.
Like Isla, Sheryl opted for metallic accessories, sprucing up her dress with gold Saint Laurent platform heels and a glitzy clutch.
We reckon Isla's subtle accessories and smooth barnet gave her the edge over Sheryl, but who do you think looked best? Let us know by voting below!
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