Watched the trailer and still don't know what it's about, but it does look dark and depressing.
Very good show. Nine episodes well worth watching. Very good acting.
There are two storylines.
One follows a detective from London, DCI Carl Morck, working for the Edinburgh, Scotland metropolitan police department.
Wherever he goes, Morck is always the smartest person in the room. But he's also the biggest asshole in the room.
Morck and his partner are investigating a murder scene with a rookie when a masked gunman comes out of nowhere and shoots all three, killing the rookie, paralyzing Morck's partner, and wounding Morck.
When Morck returns to the office, no one is pleased, so his boss throws him in the dungeon and throws away the key. But he keeps escaping, though he is quite happy in the dungeon.
Morck is put in charge of "Dept. Q", which probably comes from the lettering on the doors of the dungeon. Dept Q is tasked with solving cold cases.
Morck is given a giant pile of cases to choose from.
Morck is provided an ex Syrian policeman, Akrim Salim, with a shadowy past and unorthodox interrogation methods.
He also receives a bubbly woman, DC Rose Dickson, with a gigantic cloud of red hair that somehow manages to stay afloat. She suffers from OCD and PTSD.
This ragtag team chooses a cold case which, if they solve it, will make a sensational news story and make the cold ***** they all work for look good.
The second storyline follows a female prosecutor, Merritt Lingard, as she tries to put away a man who allegedly threw his wife down the stairs, killing her.
Lingard is a very good prosecutor who has put away a lot of bad guys, but she bungles this case and receives a spanking from her superior with a superiority complex.
Lingard has a younger brother, William, who was normal until he was mauled by a home invader who beat William so badly he became mentally disabled and mute. But he is an art prodigy. The boy can draw.
I must stop here to say Merritt Lingard has, by far, the most awesome leather overcoat I've ever seen on a woman.
The show switches back and forth between these two seemingly unrelated stories until the very end of the first episode when the connection is made in a somewhat surprising way.
You will enjoy this show. Seriously.