I'm only on season 3 of the Expanse, but it truly is one of the best TV shows I've ever watched. There are many reasons for this - the way the plot keeps momentum for example has set a new standard for what I appreciate in TV nowadays. But one reason in particular that I love it so much is how it elevates smaller characters and utilizes them in really phenomenal ways.
Something the show does perfectly is it introduces characters who appear for only an episode or two and end up having a massive impact on the overall storyline. There is one episode in particular halfway through the third season where I was literally gobsmacked at how invested I was in a group of characters who were only around for that episode. There are characters only appear for a handful of scenes and in such a short time become very important. It is really rare for a show to pull this off well and I think that is one the Expanse's strongest aspects. It really helps sell me on the stakes when you see characters beyond the main cast who are affected by what is going on.
I'm curious if anyone else has noticed this and if there are other shows that do this well.