More than 20 years after he shot to fame on Pop Idol in 2002 Gareth talks about the new musical he is penning which is all about stammering. He has an overt or exteriorised stammer which causes him to get stuck at the start of a word and repeat the initial letter.

Former politician, Ed, didn’t realise he had a stammer until he was already serving in Gordon Brown’s government. He has a covert stammer and describes it as a “block” which means the right words don't always come. He reveals the impact it had on political life when his rivals used it to rock the public’s confidence in him and the moment he knew he had to go public.

Presenter: Emma Tracey

Producer: Alex Collins

Editor: Beth Rose

Sound: Dave O’Neill and Daniel Gordon