Gareth Malone is set to coach eight people with no classical choral experience to sing Handel's Messiah.
The choirmaster's new BBC project will see the recruits perform alongside the BBC National Orchestra of Wales and Chorus of Wales at Cardiff's Llandaff Cathedral.
The concert, in aid of BBC Children in Need, will be the first time Mr Malone has conducted a performance of the nation's favourite choral work.
Mr Malone said: "Handel’s Messiah was one of the very first concerts that I went to as a child with my parents, and it’s a work that my Welsh grandmother sang in a choir.
"So, I am shouting Hallelujah to the rafters to be sharing this magnificent work with eight complete newbie choral singers."
The chosen eight are Foo Seng, Nia, Harry, Rosie, Aaron, Ami-Louise, Naomi, and Richard, all of whom have personal stories and motivations.
Naomi, who has been diagnosed with secondary breast cancer, said: "This opportunity shone a great deal of light into those dark weeks of winter.
"The beauty, joy and catharsis that I found in listening to and participating in Handel’s Messiah had such a positive impact on my mental health and state of mind."
The series will air on BBC One and BBC Two over Easter.
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