Spoilers for the first season, this is your only warning
I'm currently rewatching this in celebration of Halloween.
This is one of my absolute favorite shows, definitely top fifteen.
This show is Gothic horror in 1890s london. The Main Characters are Vanessa the woman tormented by otherworldly forces, Ethan Chandler (spoilers real name Ethan Lawrence Talbot with all that entails) The Heroic American Gunfighter from The New Mexico Territory and you can probably guess what else ,Victor Frankenstein who well is victor frankenstein only this time he is English not swiss, Malcolm Murray (Mina Murray's Father and played by Timothy Dalton) The Bold Explorer who is less Indiana Jones heroic styled and more Christopher Columbus murder your way across Africa styled but is looking to right his wrongs.The Irish hooker dying of consumption Brona Croft played by Billie Piper. Sembene the African Manservant who is more than he seems, Dorian Gray who is well Dorian Gray, and Caliban aka frankenstein's monster.
The biggest goal of the first season is to kill or save Mina Murray as she has been turned into a vampire by well you can guess.
The show actually is rather scary at times. The first time that I really got into the show was the second episode with the Seance scene. It takes a lot these days to make a possession scene absolutely terrifying but they managed to make it so. The other achievement is to make any scene with a nude Eva Green Terrifying. Let me Repeat, NUDE EVA GREEN. TERRIFYING NOT SEXY. I wasn't aware that was possible till this show.
I also rather like how they portray each character. The heroes are likable but flawed the villains are evil and scary.
In short this series is fucking awesome and you should watch it.