Fresh from her stunning performance at the Super Bowl XLIX last weekend, the 'Firework' singer waved goodbye to her black, raven locks in favour of a much brighter hue for the 57th Grammy Awards on Sunday night (8 February).
Katy was nominated for Best Pop Duo and Best Pop Vocal Album at this year's awards and later performed her ballad 'By the Grace of God' to a star-studded audience at the Staples Theater in Los Angeles.
The 'Roar' starlet is known for dabbling with rainbow-coloured locks, having experimented with everything from electric blue to "slime green" over the years.
But other than a temporary warm purple colour job in December, Katy has pretty much stuck with her shiny black hair colour in recent months.
On Sunday, however, the deep black locks were gone and in place Katy had opted for a very Kelly Osbourne-esque lilac hair colour which she wore in a shoulder-length, wavy bob.
We love the way Katy kept her roots dark in a grungy, rock-chick kinda way.
And in an amazing silver Zuhair Murad dress, along with dripping diamonds and a cheeky nose ring put together by celebrity stylist Johnny Wujek, she really did sparkle on the red carpet.
"I wanted to shine like a diamond," she said in an interview with Ryan Seacrest on E!'s Live on the Red Carpet.
And shine she most certainly did.
What we didn't realise, however, until we saw her perform later in the evening, was that Katy was actually wearing a wig on the red carpet.
As she took to the stage in a floor-length white gown, her black hair had returned and was tied back into a low, sleek ponytail.
The cheeky minx! Bring back that lilac bob Katy, we loved it...
Watch Katy perform 'By The Grace of God' below.
What do you think of Katy's new lavender do? Let us know below. Our fave comment across the site each week wins £50!
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