Stargate Atlantis/Recap/S02 E14 Grace Under Pressure

"Why? Because you are an inanimate object! Does that stop me from talking to you? Oh, no, no, no, my inanimate friend. Because I have been struck upon the head!"

- McKay maintains a surprisingly accurate grasp on the situation

McKay and particularly obnoxious Red Shirt Griffin are taking a newly repaired Jumper out for a spin to the mainland and back, when something goes horribly wrong and they crash into the Lantean ocean. They manage to call in to Atlantis, but the Jumper sinks out of radio range before anyone can accurately triangulate their position. Zelenka gets to work on figuring out where they are, while Sheppard starts outfitting a second Jumper as a sumbmersible.

Griffin and McKay's Jumper is sinking fast, and the external pressure is taking its toll on the windshield integrity. McKay and Griffin retreat to the back half of the Jumper - where they can't close the door. Griffin elects to close the door from the outside, sacrificing himself and leaving McKay alive, alone, and in the dark, with a bleeding head wound. The rest of the episode is him feaking out in a closed room until Sheppard comes and rescues him.

After McKay has managed to relieve some his pressure by yelling at himself, the Jumper, his laptop, Zelenka (who refused to fly the thing) and a passing whale, he gets down to the business of making sure he has enough oxygen and won't freeze to death. Against Carter's advice, he also starts on a plan to surface enough to boost his distress signal, at the cost of most of his remaining power. Wait, against whose advice? Oh, it's Col. Carter, dressed in a bright pink take on the Atlantis uniforms. She calmly explains that she's most likely a manifestation of McKay's subconcious, brought on by his concussion - but not to worry, everything else is real. McKay, in turn, raises the reasonable question that, if she's his fantasy, how come she's wearing clothes?

Despite his urgings, Carter remains depressingly true to life, offering helpful advice on his personality problems, the reasons there is no chance they would ever be a couple, and how to stay alive in a sinking Puddlejumper with limited energy remaining. In particular, she opposes his plan to try to surface, saying that instead he should sit tight and let himself be rescued. And then the Jumper hits bottom, and begins to take in water. Which Carter swims in. McKay goes ahead with his plan anyway - which fails, leaving him with no power up to his waist in freezing water in a lost Jumper on the bottom of the sea. On the upside, Carter has finally consented to take her shirt off.

Sheppard and Zelenka finally manage to get a Jumper more or less seaworthy and start scouring the oceans, finding nothing but the occasional whale. Fortunately, said whale is going around and around in circles centered on a specific point. Sheppard investigates and finds - the downed Jumper! Apparently the whale took McKay's earlier urgings to go find help for him seriously - and does he say thank you? Of course not. Zelenka has prevented the second Jumper from imploding by modifying its cloak into a shield. When they get close enough, they just extend the shield around the downed Jumper, and McKay walks on out across the sea floor, waving a brief goodbye to Carter as he goes.

Tropes
"McKay: You're the worst hallucination ever!
 * Almost Out of Oxygen: briefly, but he fixes it.
 * Atlantis Is Boring: The Lantean Ocean, which covers most of the planet, contains...whales. Or, as far as we can tell, exactly one whale. And nothing else.
 * The lack of sealife on an oceanworld is later explained... but the reason why is definitely not good.
 * Badass: Griffin. While Rodney is panicking and berating him as the Jumper sinks, in 10 seconds, Griffin doesn't even hesitate to go into the cockpit, wish him luck, and then close the doors and sacrifice himself to save Rodney, before Rodney even figures out whats happening.
 * Berserk Button: Griffin, you should never assume that Rodney's knowledge is "wrong"... ever!
 * Bottle Episode
 * Cross Referenced Titles: With "Grace" from the seventh season of SG-1.
 * Double Meaning Title: In addition to the obvious, this episode is basically the SG-1 episode "Grace," under pressure.
 * Hard Head: averted. McKay's knock on the head in fact drives much of the plot.
 * Hidden Depths: Griffin may appear to be a Red Shirt taxi-driver of a Puddle Jumper, but apart from the occasional gap in knowledge, does raise some rather good philosophical questions about science and if McKay ever feels depressed that later generations might consider his theories "wrong"
 * Heroic Sacrifice: Griffin
 * Informed Self Diagnosis: McKay diagnoses his hypoxia with enough time to do something about it.
 * Kiss Me, I'm Virtual
 * Ominous Crack
 * Recycled Script: From "Grace," as the writers are well aware.
 * Space Whale
 * Stock Episode Titles: A comparatively minor case, currently coming in at 5 uses.
 * Talking to Themself: Elements of this whenever Carter reminds McKay that she's just a manifestation of his subconscious mind.
 * Worst Whatever Ever: When Carter steadfastly refuses to act like a proper fantasy

Carter: Oh, you don't mean that!"