Olly Murs has announced that he's taking on a mammoth challenge in memory of his much-loved friend Caroline Flack.
The Voice coach is joining a group of Caroline's close friends and family on a mountain trek to raise money and awareness for Samaritans to honour his late friend.
Former Love Island presenter Caroline tragically took her own life at the age of 40 last February.
Olly, who presented the X Factor with Caroline in 2015 after they co-presented its sister show Xtra Factor, shared a photo of the friends pulling funny faces at each other as he revealed he was climbing 24 peaks in 24 hours for the suicide prevention charity.
He wrote on his Instagram: Hi guys, I'll be taking part in #Climb4Caroline in memory of Cazza this weekend.
"A few of us will be trekking 24 peaks in 24 hours to help raise awareness and hopefully help raise vital funds for leading suicide prevention charity, @samaritanscharity.
"If you'd like to support click on the link in my bio!"
Pop star Olly, 37, who shot to fame when he came second on The X Factor in 2009, was flooded with loving messages following his announcement.
Fearne Cotton sent a stream of love hearts and Laura Whitmore, who took over the reins from her friend Caroline as Love Island host last year, also pressed the button on a love heart emoji.
And Caroline's close friend Lou Teasdale, who is also taking part in the trek, shared a hiking boot emoji in solidarity.
"Thank you for your support, Olly," said the Samaritans.
"You're doing her proud," said one fan.
"She'll be proud of you," said another.
In March Olly, who is part of the star-studded line-up taking part in Soccer Aid at Manchester's Etihad Stadium in September, spoke movingly about his friend on The Channel 4 programme Caroline Flack: Her Life and Death screened in March.
He opened up on how Caroline was deeply hurt and 'affected every day' by the abuse levelled at them when they hosted The X Factor.
The duo were given the chance to step up to the main show when they replaced Dermot O'Leary for a year.
Away from the cameras they were blighted by criticism, from the press and online trolls and Olly revealed just how much it affected the late star.
Recalling that they read that they were being sacked on the night of the live final he said: "It should have been the most amazing experience of our lives.
"But, it ended up being our downfall really.
"After the first two or three shows, we got it from all angles: 'this show is good but it’s missing something, it’s missing Dermot’ and all of a sudden you’re just boom, beaten up again.
"It was constant for ten weeks, it was always 'what are the media going to say now? what have people said on Twitter now?’
"The abuse she was getting, it was awful."
Caroline's former personal trainer Bradley Simmonds is leading a party of intrepid trekkers walking for 12 hours each day taking on mountains across the Lake District from Friday 11 to Monday 14 June.
Bradley said: "I was Caroline's personal trainer and good friend. I was devastated by the loss and still am.
"I know how much exercise helped Caroline with her mental health so I wanted to create a challenge where her family and friends can come together and do something powerful in her memory.
"Hopefully this challenge will raise awareness for others to seek support whilst also raising money for Samaritans".
Every £5 raised for the Samaritans will answer a call for help around the clock 365 days a years.
Call free on 116 123 (within the UK or Ireland) or email jo@samaritans.org.
To donate visit justgiving.com/fundraising/climb4caroline
