- You don’t understand, Doctor: things have changed around here. The Asgard are in the process of fitting Prometheus with engines capable of reaching other galaxies. We were mapping a mission to find out what happened to you.— Walter Harriman explains the feasibility of travel to and from the Pegasus galaxy
The team discovers a planet full of nothing but a fog-like substance and strangely constant energy readings. McKay realizes that the gate draws energy directly from the not-actually-fog — and the planet is covered with it. This near-unlimited energy supply opens up a previously unthought of possibility: dialing earth.
Not without effort, of course. McKay first has to unhook the control crystals from the Atlantis DHDnote that allow it to dial an eighth chevron, and then successfully reattach them to the device on the planet. What could possibly go wrong? Fortunately, it's only 840 years by Puddle Jumper from Atlantis if something does go wrong. But it doesn't, and our heroes are delighted to hear Walter's voice come through the Stargate from the SGC. He assuages their worries that it might be a one-way trip — anyone who steps though could be back in the Pegasus galaxy inside of a month.
So, of course, they all do. And Earth is really great! General Hammond is back in charge of the SGC for some reason. Teyla learns about shopping. Sheppard has a really sweet bachelor pad and a pizza party. Dr. Weir gets to have some awkward conversations with her boyfriend Simon from the first episode. Dr. McKay manages to score a hot girlfriend and some really ugly t-shirts. And Ford... does... something.
It is not long before problems start to arise. There is a horrible accident on the Prometheus, making return to Atlantis impossible. McKay immediately starts a scheme to see if he can squeeze some life out of Earth's ZPM, but nobody is interested in helping out. Meanwhile, Weir learns that the Atlantis mission is going wholly military — that is, she's been fired — and Ford has been reassigned to Antarctica. Sheppard's party continues to rock his sweet bachelor pad — everybody's there, including his sixth grade teacher and a couple of old army buddies who died in Afghanistan. Oh, and the laws of physics have given up and stopped working altogether. As McKay puts it, "It's like looking through a microscope at a cell culture and seeing a thousand dancing hamsters."
Weir finally gets fed up and has it out with General Hammond, who reveals himself to be an alien made up of not-actually-fog. The team have been trapped in individual fabricated realities without ever having left Fog Planet. He explains that the fog-like substance is actually the planet's population, and the Stargate draws its energy by killing them. The proposed dialing of another galaxy would have caused the death of millions. He agrees to let them go (and not starve to death while in their respective dream worlds), in return for which Weir promises to take the team back to Atlantis and never return.
Tropes
- Arson, Murder, and Jaywalking: Sheppard's annoyance that he lost his beer when the illusion ends, as well as Rodney freaking out that they're currently starving to death on the planet, since to survive human being need;McKay: We need food, we need water... I mean, we need food!
- Back from the Dead: Two of Sheppard's Air Force friends show up at his apartment for a party. They were both killed in action years ago, which is the final straw for Sheppard and confirms his suspicions that everything is fake.
- Fun T-Shirt: McKay has a T-shirt reading, "I'm With Genius," with an arrow pointing upward.
- Hyper-Awareness: Sheppard notices something is wrong with "Earth" almost immediately and according to the fog aliens, proved uniquely able to manipulate the reality given to him.
- I Never Told You My Name: Weir figures out the illusion when her fake McKay advises her to forget about Atlantis and spend some more time with her boyfriend Simon, despite Weir never having disclosed his name.
- Life Energy: The fog aliens exist as this, which the Stargate inadvertently draws from and kills thousands of them each time it opens. McKay dialing Earth would not be good for them.
- Loser Protagonist: McKay's answering machine registers no new messages after months of absence. He assumes that there must have been a power failure.
- Lotus-Eater Machine: Everything from when they reached the planet to dial Earth wasn't real. The bigger twist is that they've all been living in different fantasies (except for Teyla, who was placed into Sheppard's illusion because she had no past knowledge of Earth).
- Reality Warper: The fog aliens reveal that Sheppard was the only one able to manipulate the illusion. He promptly kicks himself over the stuff he could have imagined.
- Reality Is Out to Lunch: As a scientist, McKay almost immediately attempts to solve being stranded on Earth and comes up with a plan that will involve the nearly depleted ZPM they have. However, the test results he receives from his colleagues are all mumbo jumbo and any tests he performs himself fail, causing him to realize that the universe itself is out of whack.
- Reassigned to Antarctica: Literally, in Ford's case.
- Required Spinoff Crossover: Hammond (albeit as an alien posing as him). This also incidentally makes this episode Don Davis' only Stargate appearance outside of SG-1 (as he passed away before Stargate Universe began airing).
- Rewatch Bonus: Aside from the obvious thread-spotting that can be done, on a second viewing one might also notice subtle clues indicating that Sheppard does indeed have a measure of control over the illusion. At the SGC he gets the idea to call for a car, only to find that "Hammond" has already done it for him. Later at the bachelor pad, his two buddies arrive at the front door moments after Teyla suggests that he get in touch with some friends, then still later "Ford" shows up at the party and Sheppard says he was just thinking about him.
- Schrödinger's Butterfly: At the end of the episode McKay wonders aloud if they really are back in reality or if they're still trapped in the illusion. Then the fog yells at him.
- Shout-Out: McKay is watching The Outer Limits, which had several similar plots.
- Spotting the Thread:
- The team eventually realize the inconsistencies with their actual reality, such as physics not making sense, people acting out of character and in Sheppard's case, some of his old Air Force friends being alive again. In fact, Sheppard figures it out early on and starts adding more and more nonsense to his illusion to see how far his captors will take it.
- The incongruences between each character's separate illusions also start ramping up as the episode goes on. For instance, in McKay's illusion he dilligently tries to get the ZPM to work to dial back to the Pegasus galaxy, but he's completely disinterested in doing so in Ford's illusion.
- Averted when it concerns Hammond, which is especially egregious for Weir as she was the one who announced in the season 8 premiere of SG-1 that he had been promoted to Lieutenant General (yet his uniform only has two stars) and that O'Neill would be in charge of Stargate Command; yet, she never bothers to question why Hammond is at the SGC or where O'Neill is.
- Wham Line: When Weir remarks that it should have been Sheppard who came through, despite him and Teyla having already been shown on Earth multiple times.
