Sure enough, Gilliam seems slightly damaged himself when I meet him in Valsain. As effervescent and opinionated as he is, he is also stooped, gnome-ish and generally less manic than he appears in Lost in La Mancha. “I’m not as bouncy as I used to be,” he admits. “I don’t have the madness and strength I used to have, so when things go wrong, when things are difficult, I’m more and more willing to give up.”

He also has doubts as to whether his film can possibly live up to the extraordinary mythology which has grown around it. “The problem is that people have very high expectations,” he says. “And a lot of people say I’m a fool to make the film, and that it would have been better to let people imagine how great it would have been, rather than making it a reality and disappointing them. People love Roman ruins because they’re not complete and you can imagine them. So I may be making a great mistake. Maybe the film would be better as a fantasy.”

So what keeps him going? “It’s a medical problem. It’s not a film, it’s a tumour, and I have to have it removed. I want it out of my life, frankly.”

That was in May, 2017. With the recent word that The Man Who Killed Quixote would be screened at Cannes, it looked as if the tumour would be removed, and the film he conceived in 1989 would be seen at last. But Branco’s latest legal threats changed the prognosis yet again. At last, we now know Gilliam, Driver, Pryce and Kurylenko will be on the red carpet on the festival’s closing day, Saturday 19 May. But when it comes to Quixote, you can never know for sure - Gilliam may have won the court ruling but it was also announced on 9 May that Amazon Studios has pulled out as Quixote's distributor in the US. It's hard to dispel an aura of gloom that's been hovering for so long. As I was typing this article, before the ruling came down, the director posted a link to a news story about Branco’s intervention on his Facebook page. “This is just to keep you loyal fans up to date,” wrote Gilliam. “I may need your help. I will let you know.”

[Editor's Note 9 May 2018: This story has been updated to reflect that Paolo Branco's lawsuit, which attempted to block The Man Who Killed Don Quixote from screening at Cannes, has been thrown out by a French court. The film will screen as planned 19 May as the festival's closing-night film.]

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