When he does a work for the screen, he is immediately tempted to write out new scenes, which makes it more cinematic. I did not want to do this: we confine ourselves to one place, the apartment, which serves as a mental space. The main character lost his way due to old age and he wanted the audience to start doubting reality, realizing what it feels like when the world around you becomes believable.

What has cinema done that was not necessarily possible on stage?

I found that we can go much further to make aware of deviations and immortalize them. One of my best cinematic memories is David Lynch’s “Mulholland Drive”, and likewise, I wanted the audience to be responsible for making sense of what is happening. To create a labyrinth of sorts, we worked hard with the set designer, Peter Francis. This is why there are so many symmetrical doors, hallways, and effects.

The film was shot in a studio in London, so we were able to completely change the apartment: bit by bit, the furniture varied, the proportions, sometimes even the color. Only cinema can make it so much like a puzzle, with one piece constantly missing.

How did Anthony Hopkins react with the main character to get a script that bears his name?

I wrote the screenplay with this in mind, although I knew it was an unrealistic dream. I sent her to my agent and one day I got a call. Anthony wanted to meet me, so I took a plane to Los Angeles to have breakfast with him.

He immediately understood why the character’s name was Anthony, but he asked me if it really meant having the name and his actual date of birth in the film. I told him that it was important for me to blur the lines between fact and imagination, so that it could act as a door on itself, so that it could open at any time.

It shaped the whole process – he didn’t want us to build a character and we resorted to clichés. What mattered to him was connecting with his own death, which was very brave for him. This included facing the part of his mind that could be feared at the age of 83, which was about to come, and exploiting the feeling of fear.