A previously undiscovered safety feature in the stargate is revealed in this episode when Carter (Amanda Tapping) plans to go to one planet, but the gate sends her to a different one. It’s preventing her from traveling to a planet that is now too close to a black hole.

Carter is able to override it and SG1 head out to investigate the planet discovering a goa’uld/human hybrid in an abandoned lab. Khalek (Neil Jackson) is revived back at Stargate Command under Lam’s (Lexa Doig) careful eye, but you know it’s not going to go well.

Prototype was written by Alan McCullough and it debuted on 16 September, 2005.

Daniel (Michael Shanks) discovers that the hybrid was created by Anubis, from his DNA… in essence, his son. Oh boy.

Once Daniel lets Khalek know that they know who he is, the innocent facade drops off and a battle of wills begins. While Mitchell (Ben Browder) and the rest of SG1, and the SGC insist that Khalek is a threat, and should probably be stopped or re-frozen before he can realize his full power. And if he does that, he can ascend.

Unfortunately, Woolsey (Robert Picardo) sees the hybrid as a potential benefit, and tries to negotiate and work with him. Perhaps use him against the Ori.

Things go badly when Khalek isn’t returned to the lab, as he wants to be, where he knows he’ll be able to complete his process and the SGC is turned into a combat zone as SG1 works to stop him.

It’s a fairly basic story, revisits the ideas of Anubis and Ascension again, but it’s fun. And predominantly a bottle show. That seems to suggest the budget is going to be used somewhere else… perhaps the mid-season finale?

The Fourth Horseman: Part 1 is the mid-season finale. Damian Kindler penned it, and it was first broadcast on 16 September, 2005.

Gerak (Louis Gossett Jr.) is meeting with the Ori! And he makes the promise of introducing the Book of Origin to the Jaffa. Gerak clashes with Bra’tac (Tony Amendola) and Teal’c (Christopher Judge) over this and the future of all free Jaffa.

At the SGC, discussions of the Ori continue, but they aren’t ready when the Ori release a plague on Earth! And help for Earth and the SGC comes from an unexpected quarter. Remember Orlin? He doesn’t look like Sean Patrick Flannery anymore – he’s a young boy now played by Cameron Bright.

Lam is working hard to figure out a way to stop the plague that has broken out of the SGC and is spreading faster than a quarantine can be set up.

Orlin warns them that the Ori must be stopped. They pose a threat that the SGC hasn’t prepared for as more and more worlds fall to them. He also believes that the Priors don’t know the true motivations of the Ori that they serve. And that problem is augmented by the alliance forming between some Jaffa and Ori.

But there’s also something wrong with Orlin, and he probably won’t be ascending again (and he still has feelings for Carter).

Oh and hey! Hammond (Don S. Davis) makes an appearance! Dr. Lee (Bill Dow) shows up as well. And Julian Sands makes an appearance as The Doci as Gerak goes to meet them.

We race towards a To Be Continued that sees a nation wide quarantine placed in effect, Mitchell and Daniel are captured by former allies, Teal’c argues for the freedom of the Jaffa over a commitment to Origin which concludes with Gerak arriving as a new Prior!