“Ethon” is episode fifteen of season nine of Stargate SG-1.
Jared Kane of the Rand Protectorate, one of two nations that SG-1 accidentally caused a war between in “Icon”, activates the stargate and asks to come through to the SGC.
Nothing had been heard from the planet in months. Apparently, a Prior of the Ori had come through the gate and, in return for their worship, he gave the Rand Protectorate the plans to build an orbital weapon. Which has been built, and used.
Kane wants the weapon destroying. Daniel offers to talk to his government first, and explain the true nature of the Ori, to see if they can be convinced to dismantle the weapon themselves.
Things don’t go to plan. Daniel and Kane are locked up, and the orbital weapon has way more capabilities than thought, and the Prometheus is destroyed.
With Daniel captured and the Prometheus gone, options are very limited.