IMDB only lets you do one review for a show and I think it is only fair to review it as a whole.
At it's best, Orphan Black it a tense, intelligent, dystopian sci-fi thriller. But ultimately, the complexity of the story becomes unsustainable.
Seasons 1&2 are fantastic and would rate a 9/10 if the show had stopped there. There are a couple of episodes that miss the mark, but the rate of story development is so fast that they don't linger on the weak points. It's a tense, mysterious drama about a group of female clones who have grown up with no idea of their background, and who now have various dark forces trying to control them.
Season 3 takes a markedly different direction, with a more military setting and another group to focus on. It's not bad, but it loses some of the focus and believability that made the first two series such a success. 7/10.
Season 4 does an amazing job of ret-conning almost all of the events in Season 3, and goes back to the urbanised, commercial dystopianism of the first two seasons, with an increasing number of flashbacks to explore the characters stories in more depth. However, when you are effectively re-telling a different version of the story in Seasons 1&2 it's hard to make a big impact. 7/10.
Season 5 is where it all falls apart. The writers very cleverly left little nuggets of information in earlier seasons which weren't fully explored. This season tries to bring them all together, and neatly tie up all the loose ends, both in terms of the storylines, and the characters that have been involved. It's too optimistic an undertaking and it just doesn't work. The psychological tension is mostly replaced by gore. Many of the rules that rooted the show in a degree of reality previously are broken. It's a step too far into fantasy, and it's a chore to get through. 3/10.
Tatiana Maslany is exceptional - granted a couple of the characters are a bit annoying (Sarah/Cosima)- but some of them are fantastic creations (Helena/Alison/Krystal). The brilliance of the performance is that she includes little details that mean you know who is who, even when their hair and clothing are hard to tell apart.
The show is bold enough to get rid of key characters. It's a risk that a lot of shows aren't willing to take. Unfortunately the cast and characterisations in later series is not as strong as at the start.
Long running dramas like Orphan Black always suffer from the same problem. There is a great story to be told in 10 episodes. But if the audience likes it, they will want more of it. The networks will want more of what the audience wants. And the writers would be fools to say no to another 3 months production budget. Which means that "jumping the shark" becomes inevitable - at some point you will run out of good material to extend the story further.
Orphan Black did really well to keep the quality up for 4 seasons. And were wise enough to end it in the 5th.
