The Blockheads frontman, who died of metastatic liver cancer in 2000, is played by fan Serkis in upcoming biopic Sex & Drugs & Rock & Roll.
Serkis told The Guardian of their meeting: "He was obnoxious. We were in a Chinese restaurant and he slagged everybody off and was just an arse, you know.
"And that same night, Mickey Gallagher, who was one of the Blockheads but was caring for him, just went, 'F**k this, I'm not doing it anymore', and he left Ian on the pavement outside the hotel."
He added of the movie: "I knew we weren't going to be painting a glorified picture of a stoic underdog, it was going to be warts and all.
"When we started showing early drafts to [Dury's second wife] Sophie and [eldest son] Baxter they were like, 'He's so much darker, so much more of a c*** than this. You've got to get down and dirty with this'. So we thought, great, if they're prepared to take off the boxing gloves, so will we."
Serkis continued: "There isn't a moral to the story, but it's like, be magnificent in the short amount of time you've got. And I think I live my life by that code, but we also have real life to deal with.
"Where the Venn diagram crosses over between me and Ian is wanting to do the very best you can in the short space of time you've got, but give everything you can equally to the people you love and who are your life. That's a really difficult thing."