I recently picked up the first two seasons of Alias in the summer sales, and I have been having a good time watching those recently. It is a fine show, with lots of double-agent tension and cliff-hangers.
However, the reason I have been looking forwards to watching more of this is due to one episode. Quite possibly, the greatest single episode of any show I have ever watched. Alias, series 2, episode 13, "Phase One".
This is not really a stand-alone episode that I could recommend to anyone. Instead it is the climax of almost evrything the show has been so far, and twisting the concept so completely that it takes everything into a new direction. It is tense, and dramatic, and full of action, and left me with an indescribably huge buzz.
I have not heard the best fo things about the shows third season, but having enjoyed the first two so much, I think I may have to go ahead and watch it anyway.