I thought the first two seasons of Continuum were very well done. The viewer is kept guessing as to which side is winning, or whether either side is having any effect on their future at all. The characters have plenty of personal issues to keep things interesting, in addition to the big picture. But I was less enthusiastic about the third season and the short six-episode fourth season, largely because the writers introduced actual timeline changes. In most of the first two seasons, the viewer was never sure if anything in the future had actually changed, or if everything we saw was just part of a big causality loop. At the end of the second season and into the third, though, it's very clear that things are actually changing. Once that started happening, I felt that a lot of the suspense went out of the plot. (Also the ending is fairly sappy, but I don't hold that against the show since they had to wrap everything up in that short final season.)
There's a lot of the usual suspects in the plot of Continuum: nearly magical future technology, lots of hiding from present-day characters, future people trying to protect their ancestors, and so on. For the most part I thought all that stuff was handled well, if not in a particularly original manner. That's OK, since the real originality of Continuum comes from how the characters change their views about what the future should be like over time.
For anyone who loves sci-fi based dramas, Continuum is worth watching. It's really good at the beginning, and by the time it starts to slow down you'll likely be invested enough in the characters and plot to forgive the weaker portions of the later seasons.
