Dame Barbara Windsor is set to front her first project since disclosing she has been living with Alzheimer’s.
The 80-year-old former EastEnders actress revealed in May she was diagnosed with the disease in 2014.
Dame Barbara will host the first episode of Double Acts, a BBC Radio 2 documentary series exploring the histories of great comedy partnerships.
Her episode, which was recorded in April, will tell the story of US comedy duo Bud Abbott and Lou Costello.
The pair were stars of radio, TV and film in the 1940s and were best known for their “Who’s on first?” routine.
“I remember watching Abbott and Costello in my teens and I absolutely loved them,” said Dame Barbara.
“I’m happy to pay tribute to them as two of America’s leading funny men.”
Radio 2 boss Lewis Carnie said: “As one of entertainment’s national treasures, I was delighted when Barbara agreed to narrate this documentary profiling one of the world’s most talented double acts.”
Her episode of the four-part series was recorded shortly before she made her diagnosis public.
Dame Barbara’s husband Scott Mitchell told the BBC earlier this year his wife had been taking medication to manage her condition.
Other episodes of Double Acts will see Christopher Biggins tell the story of British female comedy act Gert and Daisy, and theatre and film producer Bill Kenwright pay tribute to Dean Martin and Jerry Lewis.
Michael Crawford completes the quartet with an episode about classic Hollywood double act Stan Laurel and Oliver Hardy.
The first episode of Double Acts will be broadcast on 25 July at 21:00 BST.