Thespian Celia Imrie, EastEnders star Tameka Empson, Line of Duty actor Mark Bonnar also feature alongside Paloma Faith, Charlotte Church, Cat Burns, Professor David Olusoga and YouTube prankster Niko Omilana.
Comedians Joe Wilkinson, Lucy Beaumont and Nick Mohammed round off the line-up, with host Claudia Winkleman also returning.
Contestants will compete for a £100,000 prize for their chosen charities.
The nine-episode series, filmed in a Scottish castle, is set to air this autumn.