During his sentence in Reading Gaol, Oscar Wilde wrote a letter to his lover, agonising over the lack of contact. It is perhaps the greatest love letter ever written, filled with a torrent of accusation, passion and eventually reconciliation. A century later De Profundis remains an astonishing tour-de-force of self analysis. Reviving his National Theatre performance from 2000, Corin Redgrave reads De Profundis.