We live in an age dominated by leaks. The plot of Game of Thrones season 7? That leaked eight months before the first episode aired. Every little detail about the iPhone X? Leaked. The Galaxy S9 isn't due to be launched for at least another month and we already have a very good picture of what it will include.
So it's kind of a miracle that there were no plot leaks for Star Wars: The Last Jedi. You can probably attribute that to Disney keeping it's new cash cow franchise closely under wraps, but you can't ignore the measures writer/director Rian Johnson took to make sure drafts of the script didn't end up in the wrong hands.
Speaking to the Wall Street Journal, Johnson revealed the, frankly, pretty simple things he did to make sure nothing went horribly wrong:
“I typed Episode VIII out on a MacBook Air. For security it was ‘air-gapped’ — never connected to the internet. I carried it around and used it for nothing except writing the script. I kept it in a safe at Pinewood Studios. I think my producer was constantly horrified I would leave it in a coffee shop.”
If that sounds familiar, it's not too dissimilar from what George RR Martin does with A Song of Ice and Fire - the difference being he uses an old DOS machine that can't physically connect to the internet. And because it's not portable he can't write when he's on the move, much to many a fan's disappointment.
No internet connection means your machine can't be remotely access by hackers hoping to make some money, and it significantly reduces your chances of being infected by malware. It's not totally clear whether he did take it to coffee shops to write, but that would be a bit of a risk. Not just for accidentally leaving it behind or being mugged, but also in case some nosy latté-enthusiast was secretly watching his screen.