The main problem with Eureka is that it can be hard to work out what's going on, I'd seen occasional episodes on TV which were all jumbled up - some new, some re-runs - and hadn't liked the look of it at all. Then I saw a really good episode, made a note to watch the next and just like flipping a switch, I was addicted and bought the whole lot. And LOVE it. So this was my Season 4.5 purchase, and while perhaps the earlier seasons were better, I've watched this a couple of times already. If you're a Eureka fan, you weren't even looking at this review. If you're new, start at the beginning and watch them in order. Brilliant stuff.