John L Williams talks to Jamie Owen and Lisa Rogers of BBC Radio Wales about his new biography looking at the troubled early years of Dame Shirley Bassey.
Williams, who has won acclaim for his gritty novels based in Cardiff's docklands, says he was surprised to discover that Shirley's childhood was even more troubled than is generally known.
Her mother had a series of illegitimate children before marrying Shirley's father, a Nigerian sailor.
The couple split up when Shirley was two years old - Williams discovered that Henry Bassey had been jailed for child abuse and was later deported.
The book also details how Shirley overcame teenage pregnancy and racism to become a star by the age of 18.
Miss Shirley Bassey by John Williams is published by Quercus.