I really liked the first season, maybe because the main problem wasn’t that obvious there as it was still fresh and new. But the rot was already sitting deep. Alias is some kind of spy-themed action series fused with the structure of a soap opera.
As I said this isn’t really obvious from the beginning, but as I reached the start of the third season I was completely sickened by the emotional flip-flopping of the main character and other characters as well (without any real character development), the constant desire for new shocking twists and revelations that made each new episode more ridiculous than the last (and not really much sense if you spent more than two minutes thinking about it), the deus ex machina nature of Rambaldi and his artifacts and other stuff. I haven’t seen more than the first two and the first half of the third season, so it may have gotten better or not. Can’t say, as I felt like I had wasted enough time on that crap.