If Richard Linklater maintains his track record of releasing a Before movie every 9 years, we will have one in 2022. 

That seems unlikely, though. He wants to keep it at 3. 

Ethan and Julie in before sunrise
Source: Lithub

And that is probably a wise idea; because at no point do I see us going 'okay, we know enough about Jesse and Celine now'. 

So it's good this way. We can do whatever we want with the characters because they are now only in our heads. We can put them back in Paris, we can send them for a trip to the city where they first met, and we can make them talk. I often make Celine say things I can't.

ethan and Julie in before midnight
Source: Indie Wire

That is the charm of the trilogy, behind which is genius of Julie Delpy and Ethan Hawke, who contributed to the script and the dialogues besides acting of course. In fact, it might come as a surprise but they were the ones who came up with the names of the characters. That's something I learnt from their recent interaction with TIFF (Toronto International Film Festival) on YouTube Live.

9 years after the release of last installment, Ethan spoke of the process and 'ferociously intelligent' Julie. He also shared this interesting conversation between her and Richard. She thought that the script was boring and that they should hire more 'joke writers'. To which the director said:

Then, he elaborated how they wanted to keep the movie timeless, so they avoided putting in a lot of elements which could indicate the era in which it was shot. However, technology beat them in one department. 

Ultimately, he revealed that when he is stuck in a situation, he tries to think what Jesse would do if the two switched places. And that led him to a fantasy which fits the current state of the world. Before Quarantine, as he likes to put it.

Meanwhile in a separate interaction a few days later, Julie shared Celine's anguish in Before Sunset. She said that while Jesse went on to write a book and share his pain with the world, the young girl he left behind could not do that and so, when they met, she burst out.

She also noted how they'd often joke about sex while writing the script and 'boom, romance'.

Finally, she gave an insight about the process of the two actors. A lot of scenes which seem so natural, we think were improvised, they actually rehearsed them for hours. Until there was no flaw whatsoever and the words flowed as if they were just being thought by Jesse and Celine.

From Ethan being advised against doing the movie to Julie not relating much to Celine, the two discuss a lot in these videos. You can watch them here: