The BAFTA-nominated series features a group of curious interviewers -- who are autistic, neurodivergent and/or learning disabled -- posing their distinctive questions to well-known faces.
The second series got under way earlier this month and has already played host to the likes of national treasure Sir Stephen Fry, former Scottish First Minister Nicola Sturgeon, comedy legend Sir Lenny Henry and Motherland actress Anna Maxwell Martin.
The names of the other celebrities participating in this series were confirmed back in March, though Rylan's involvement has only just been announced.
David Smyth, entertainment commissioning editor at ITV, added: "The Assembly are raring to go and with such a unique mix of famous faces to interview, they will have a ball coming up with their next set of questions.
"These celebrities really do need to be ready for anything," he continued.