The Great Celebrity Bake Off for Stand Up To Cancer airs the inaugural episode of its new series on Tuesday night with Star Wars actor Daisy Ridley, X Factor winner Alexandra Burke and comedians Rob Beckett and Tom Allen.
The four stars will have to bake their way to the top to impress GBBO judges Prue Leith and Paul Hollywood.
The first batch of contestants are tasked with making millionaire shortbread, as well as a fruit tart.
For the final showstopper challenge, they have to depict their pet hates in cake form - with Ridley attempting to create an edible toilet.
Matt Lucas is hosting the series on his own as Noel Fielding is absent while on paternity leave after he and partner Lliana Bird welcomed a second daughter, Iggy, last August.
Burke has previously said she was motivated to take part in the programme because her grandfather and aunt died of cancer, while her ex-boyfriend was also diagnosed with the disease.
She said: “You’re sadly never far from someone who has cancer or is experiencing cancer in their life. That breaks my heart.”
There are 20 famous faces competing in total, so it looks as though there will be five episodes of the series with four in each.
Other celebrities take part in upcoming episodes include Little Mix's Jade Thirlwall, actor James McAvoy and comedians John Bishop and David Baddiel.
The Great Celebrity Bake Off for Stand Up To Cancer airs on Tuesday at 8pm on Channel 4.
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