'Like all of us, there was that initial worry back in March ,' says Glennie. It is the result of dozens of Zoom conversations throughout lockdown, meticulously going through detail after detail, and a dig into the De Niro and Scorsese archives. Pic: The Robert De Niro archives/ Harry Ransom Center/ Coattail Publications Image: Archive pictures show how De Niro was transformed into the character. That first conversation sparked the beginning of a friendship which has led to Glennie's latest work, Raging Bull: The Making Of, featuring not just De Niro sharing his memories and photos, but director Martin Scorsese and other stars and crew members, too - including the rarely interviewed Joe Pesci. But his father is Mr Robert De Niro, the star says.

This was the Robert De Niro, a childhood hero, one of the most revered actors in the world. For Jay Glennie, a writer from Essex who had first tried his luck emailing representatives for the star towards the end of 2016, it initially felt strange.

When you're chatting to Robert De Niro, you're told to call him Bob. For the past year, British writer Jay Glennie has been working with De Niro and Scorsese to tell the story of how the film was made. Raging Bull, the dark and unrelenting story of violent boxer Jake LaMotta, is widely considered among the greatest films ever made, and certainly one of actor Robert De Niro and director Martin Scorsese's finest works.

Raging bull the making of jay glennie