I've loved Life is Strange. It was a game unlike any other out there with completely relatable and genuine characters, an awesome story and so many hard decisions to make. Totally captivating.
It had just one flaw (in my opinion, caution: minor spoiler ahead): It started as a quite realistic highschool/coming-of-age drama and evolved into a psycho-thriller and then into some sort of supernatural mindf*ck. It still was a masterpiece, but not really what I expected.

Before the Storm is different. There's nothing supernatural and the whole story is very grounded. Such a game is not easy to find.
The characters from the original game were brilliant - but the prequel manages to develop it's main character Chloe even further and extend this character to a whole new level. Every decision you have to make, no matter which you choose, is fully reasonable and the events following are conclusive. And this helps us understand Chloe's character we already knew better. Everything not only adds up to the finale of Before the Storm, but to the events from Life is Strange, too.
The dedication to detail is incredible, because in a way you're building the scenes for Life is Strange. Replaying the original game after Before the Storm is absolutely worth the time, especially because you've got a new angle on Chloe and now know who Rachel was.

There is really nothing more to write here. You'd be a fool not to play it.
Best game of 2017
10/10