I came late to this party and ended up only watching the 1st 9 episodes of season one before I discovered the murder of Rosie Larsen would not be solved until the end of season two, and I simply couldn't take it anymore.
Where to start?
Plot: As stated, the 1st two seasons revolve around ONE murder case. There is no murder case in the history of murder that requires 20 HOURS of film to tell. That means exactly what it sounds like: this plot is dragged out to the nth, agonizing-est degree. There are twists upon twists which in theory should make the story interesting, but instead, because there are so many, eventually it becomes obvious that few of the twists do/will actually matter in the grand scheme of things. At one point, terrorism comes into play. And guess what? Terrorism doesn't have diddly to do with the murder of Rosie Larsen. That's what happens when your story's overwritten.
Characters: We've got a veteran female detective (Linden) and a young, male rookie detective (Holder). Linden seems like she's used to working alone. She doesn't communicate well. She doesn't like having to "babysit" this new young, dude. Oh, and she's a single mom. Yes, the writers really broke the mold with Linden's character. Holder's eager, he doesn't care about the rules and has a graveyard of skeletons in his closet, but we know deep down his heart's in the right place (get the bad guy by any means necessary, evidence be damned!). Again, really went for originality. And if these cliched archetypes of cop show standards weren't boring enough, both Linden and Holder make the most asinine choices possible every chance they get. Their behavior defies logic and is manufactured drama at its worst. For example, Linden is engaged to a man who wants to move her and her son to California. All Linden has to do is get on the plane. Literally nothing is stopping her from doing that, but instead, she just won't go. Why not? Who the hell knows? Does she not love him? Don't know. Does she not want to marry him? Don't know. Does she not want to leave Seattle? Don't know. Is she scared of having a normal, quiet life? Don't know. Is she obsessed with this case? Kind of, but not really considering at no point do we get the impression she's anything but a MEDIOCRE cop. So, she's not a great cop, she's a terrible partner, she's a terrible mother (stringing her kid along, back and forth with no stability), she's a terrible fiancee, and all for what? Dynamism, conflict, and tension? Yes, if we've all been teleported back to the year 1991 when such nonsensical writing was acceptable.