After starting out as an actress, Flack became one of the UK's best-known presenters and scored legions of fans thanks to her winning stint on Strictly Come Dancing.
Over the weekend, her friends, fans and colleagues were left devastated by the news she had died at the age of 40, after taking her own life.
Look back at her career highlights below...
Flack began her career as an actress on the sketch show Bo'Selecta, where she worked with TV personality and comedian Keith Lemon (played by Leigh Francis).
The star made appearances in a series of sketches about Michael Jackson, playing his "pet monkey" Bubbles.
Francis has paid tribute to Flack on Instagram, saying: "I’ve known Caroline all my telly life."
Sharing a series of images from their friendship, Francis wrote: "This morning is so odd. Looking back at fun times with teary eyes.
"It’s always nice to see a familiar face especially one so pretty or hear a familiar laugh, especially one so infectious. We had many fun times back in the day. Sweet Caroline. Will miss you".
Flack moved into children's TV on TMi, which she presented alongside Sam Nixon and Mark Rhodes for three seasons from 2006 to 2008.
Sam & Mark paid tribute to Flack's "beautiful, infectious laugh" on Twitter.
— Sam & Mark (@samandmarktv)February 15, 2020
I'm a Celebrity... Get Me Out of Here! NOW!
Flack departed TMi to take over presenting duties on I'm a Celebrity... Get Me Out of Here! NOW!, the companion series to I'm a Celebrity... Get Me Out of Here! that featured behind-the-scenes footage and interviews with contestants.
She grew close to her co-host Joe Swash, who she later joined for Let's Dance for... Comic Relief in 2011.
Dancing on Wheels
In 2009, Flack won BBC Three's Dancing on Wheels with her partner, professional wheelchair dancer James O'Shea.
The X Factor
In 2011, Flack and singer Olly Murs were announced as the hosts of The Xtra Factor, the companion show to The X Factor.
Flack co-presented the show for three years, before she and Murs were announced as the hosts for the 12th season of the main series in 2015.
Murs shared a touching tribute to Flack on Twitter, saying his heart is "forever broken."
"I haven't stopped crying since the news... we always said we was friends for life and trust me you will be with me forever," he wrote.
"My kids will know you, my grandkids will and then I'll see you again, give you a huge hug, a huge kiss, get mic'd up and have you by my side again."
Strictly Come Dancing
In 2014, Flack became a contestant on Strictly Come Dancin, and went on to win the series alongside her professional partner Pasha Kovalev.
Strictly Come Dancing paid tribute to Flack on their official Twitter account, praising her "infectious energy and passion for dance."
In 2015, Flack became the presenter of ITV's Love Island, and is credited with helping the show grow to become one of the biggest British shows of the decade.
A revival of a celebrity show that aired for two series in 2005 and 2006, Love Island saw Flack pick up the Bafta TV Award for Best Reality and Constructed Factual show in 2018.
Flack's replacement host for the sixth series, Laura Whitmore, honoured Flack in a tearful tribute on her Sunday morning BBC Radio 5 show.
"Yesterday we lost someone before their time. We're going to talk about her and give her the respect that she deserves and that she didn't always get," she said.
"Caroline, I'm so sad for you, for your family. I'm angry that you saw this as your only option as I know how much love and support you had. I'm sorry you didn't know that.
"I'm not sure when but I know I'll see you on the dancefloor again."
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