I loved primeval growing up and I was upset when they took it off air, but I know that in 2011 tv series were changing an many people weren't watching Primeval but to leave off where they did was a bit disappointing as they did leave it as a cliff hanger. I received the box set for Christmas and watched it in less than a week. The show is about creatures from past or future coming into the present and only a handful of people know how to handle them. I love series that go on about the past as I love to learn about history either the people of Britain or the animals that lived here. The only main problem I had was the show writing characters that could have a longer run such as Sarah, but the show was moving to another set and the actress couldn't go with them because of personal reasons.
I fully recommend watching this series, no review can do the series justice.