I have always loved sci-fi. I love sci-fi more than I love actual science. Sci-fi is hardly ever about science. It is imaginative and fantastic. It is always about people. For exactly this reason, Dark is a fantastic sci-fi. In its three seasons, the lives of its handful characters get deeply and inextricably intertwined and the actors performing these roles give candid performances that makes all the chaos thoroughly believable.
It is hard to make a sci-fi about time travel. If you want to make even a mildly intelligent one, you have to give up on causality as closed time loops imply fatalism. Then the question becomes that of free-will and choice, or the lack thereof. A world stuck in a loop has to be predetermined and one where humans do not have any agency and are driven by fate. But this also means that things can spontaneously happen without reason. The chicken and the egg can both exist before each other as the concept of before and after do longer exist. Dark uses this bug very creatively and creates a truly fantastic universe.
In terms of the setting and the general feel the show is very similar to Twin Peaks. Strange inexplicable things happen in a town lost in the woods. (I wonder why we like shows about small lost towns?) Instead of a dead Laura Palmer, you have a missing young german kid. You watch show just for the setting, the tension, the mystery. I honestly would have preferred if they had never resolved the series and stopped at season 2 (same problem with Twin peaks). The resolution destroys the otherworldliness of the show, makes it cheap and hard to believe.
I have fallen in love with the german language after watching Dark and would really love to watch more German cinema and television.