A line up of celebrities will learn how to swim for a brand new TV show.
Provisionally titled Sink or Swim, the Channel 4 series will see non-swimming celebrities take to the water in support of Stand Up To Cancer (SU2C).
Channel 4 say the show "attempts to erase the stigma of being a non-swimmer and follows the progress of a cast of famous faces - complete non-swimmers themselves, those with a fear of open water or those who have been taught to swim as children but now struggle to do so for health reasons – as they are pushed to their absolute limits."
The celebrities will include Olympic gold medallist Linford Christie and Coronation Street star Sair Khan.
Completing the cast are television presenter Diane Louise Jordan and Linford Christie’s fellow Olympic gold medallists, Tessa Sanderson and Greg Rutherford.
They'll team with a group of leading figures and professionals from the world of swimming who will offer vital training and support to transform them into strong swimmers, capable of taking on a series of challenges.
The experts include Olympic silver medallist Keri-anne Payne and adventurer Ross Edgley (best known for being the first person in history to swim around Great Britain), with support from Paralympic champion Ellie Simmonds.
Each of the four episodes will culminate in a punishing qualification swim and the celebrities left standing (or in this case, swimming) at the end of the gruelling training process will take part in the ultimate open water challenge together as they attempt to swim the English Channel.
The series will help raise money for Stand Up To Cancer, a joint national fundraising campaign from Cancer Research UK and Channel 4 which has to date raised over £62 million for research into cancer which will accelerate new cancer treatments to UK patients and save more lives.
Steven Handley, Commissioning Editor for Entertainment at Channel 4 said: “Sink or Swim promises to be one of the most perilous Stand Up To Cancer Celebrity Challenges we have ever attempted.
"It will push the boundaries of what Celebrities will endure and overcome to raise money and awareness for charity and we are delighted to be working with TwoFour on this ambitious project.”
Mel Leach, Executive Producer for programme makers Twofour added, “Swimming the Channel is a monumental feat for even the very best swimmers, let alone those who can’t even swim a length.
"Our brave celebrities will have to overcome their fears and embark on a huge mental and physical transformation to complete this epic challenge.”