“Line in the Sand” is episode twelve of season ten of Stargate SG-1.
Daniel is still missing after having being captured by Adria at the end of the previous episode, “The Quest: Part 2”.
The rest of SG-1 have been testing some modifications that Sam has made to Merlin’s device which was discovered in “Arthur’s Mantle” which puts things out of phase with the rest of the world.
The test goes well, so General Landry wants them to use it to hide an entire village from a Prior of the Ori. Things don’t go well; the device doesn’t work when needed, Sam is badly injured and Vala is captured by the forces of the Ori – led by her husband, Tobin.
Whilst Mitchell tries to help Sam and fix the device, Tobin and Vala are trying to convince each other that they are the one who is correct in their beliefs.