She and the X Factor judge have been pals for years, so it's no surprise Caroline has a few embarrassing snaps of the pair from back in the day.
And clearly having a good old reminisce recently, the 35-year-old found one of herself and Nick that was just too good for her not to share with the nation on Instagram...
It's only Grimmy with a perm! Brilliant, right?
In her photo, Caroline can be seen with much darker tresses than what she's sporting nowadays as she cuddled up to the Radio 1 DJ. And going for that Indie vibe, Nick is pictured wearing a checked shirt and parker with his long curly locks covering the front of his eyes.
He can hardly see!
Naming and shaming her friend, Cazza wrote alongside her post: "TBT to when @nicholasgrimshaw had a perm."
Caroline's photo comes as she and Nick are currently working together on The X Factor. While he has replaced Louis Walsh as judge, sitting alongside Rita Ora, Simon Cowell and Cheryl Fernandez-Versini on the panel, Caroline is now fronting the show with Olly Murs as The X Factor's new hosts.
The pair are currently gearing up for the Judges' Houses round of the competition, following the dreaded Six Chair Challenge.
Nick, who is looking after the boys this year, has drafted in the help of Mark Ronson, while Rita has been joined by Meghan Trainor, Cheryl by Jess Glynne and Simon by Louis Tomlinson.
Rumour has it that Nick is going to host his category in his hometown of Oldham, Manchester, shunning an exotic location due to his working commitments with Radio 1.
Rita has been filming in LA, Cheryl in Rome and Simon is said to be taking the Overs to France.
While viewers have watched Rita whittle her acts down to six in the last stage of bootcamp, the other judges are still yet to decide on theirs.
And after Rita claimed she was the "most hated person in the UK" thanks to the crowd's boos during her Six Chair Challenge, we've no doubt Simon, Cheryl and Nick's rounds are going to be just as dramatic...
Bring. It. On.
The X Factor continues this Sunday 11 October on ITV.
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