Nur is an Urdu poet and object of interest to the protagonist of In Custody, Deven, a Hindu literature teacher and would-be Urdu poet. Deven has long been an admirer of Nur and is excited to get the opportunity to interview him. Nur is built up as a character as Deven makes the journey to Delhi to meet his hero. But, as is often the case, Nur falls short of Deven's expectations. He is depicted as old, hopeless, and miserable. He tries to convince Deven to give up on Urdu poetry and accept that, as the country modernizes, Urdu will become a dead language.
While Nur eventually agrees to let Deven record him reading some of his poetry, he never really moves from his position as a disillusioned artist, convinced his time and the time of his language has passed. In Custody is a book about Deven grappling with his position as a lover of the Urdu language and its poetry in an age where Urdu seems like it will be replaced. Relative to this search, Nur represents shattered hope. It would be easy to think that if anyone knew how to make it as an Urdu poet or had thoughts about language preservation, it would be someone who had previously made it as an Urdu poet. Thus, Nur's hopelessness is quite significant.
However, we can read this not as a verdict on Urdu literature but as a commentary on looking to heroes for hope. Nur's name is recognizable because a significant audience supported his work, so perhaps it is less surprising that as this audience faded, he did not have answers for how to go forward.