Sadly, the fifth season of Stargate: SG-1 broke the streak of progressively better seasons that had been going on ever since the first season. The year began with a cool premiere, "Enemies", but the next couple episodes sucked. For example, the episode "Beast of Burden", which deals with Daniel Jackson's (Michael Shanks) Unas friend, Chaka, was terrible. Personally, I also hated the episode "The First Ones" from last year which began the Chaka thread. I mean, I haven't seen episodes this bad since Season 1 (many of the Season 1 episodes, while good, are far inferior to the episodes of Seasons 2-4). Once you reach the third disc, beginning with the episode "Between Two Fires", the episodes become good again. However, the bad episodes weren't the only problems that this season faced. Jack O'Neill (Richard Dean Anderson) seemed to regress a little bit because he seemed a lot less tolerent of Daniel than he had been in the last two years (he does, however, reveal his true feelings about Jackson in the episode "Meridian"). Teal'c (Christopher Judge) and Dr. Janet Frasier (Teryl Rothery) were underused, as were the Asgard, who seem to have put politics ahead of real problems.
However, when this season was good, it was REALLY good. There were some amazing story developments this year, beginning with the final demise of Apophis (Peter Williams), the Goa'uld System Lord who has been making life difficult for the SGC ever since the first season. Next, the Tollan, an extremely advanced race of humans who are allied with Earth, begin acting suspiciously, the SGC begins recruiting new officers, the motives of the Aschen from last season are revealed, the Tok'Ra are nearly destroyed, and the Jaffa rebellion begins to truly become a problem for the System Lords. And then, Daniel is brought to a System Lord summit where he has the chance to wipe out the Goa'uld threat forever, that is until he learns of the return of Anubis, an ancient System Lord who was banished for his horrific crimes. Also, we finally learn the origins of the Replicators. Finally, SG-1 must endure a change that they never thought would happen in the episode "Meridian", and then, Anubis and Osirus (Anna-Louise Plowman) reveal plans to attack the Asgard. But the most pivotal plot twist involves the new series-within-a-series, WORMHOLE X-TREME!!! Just kidding.
This is a very important season, so despite its poor opening, I still reccomend it. Just be ready to be underwhelmed by the first few episodes. But after you get past those, enjoy! Some good episodes include: "Enemies", "Threshold", "Between Two Fires", "2001", "Wormhole X-Treme", "Proving Ground", "Summit", "Last Stand", "The Warrior", "Menace", "Meridian", and "Revelations".