This episode is part 1 of 3; it is followed by "Be All My Sins Remember'd" and "Spoils of War".
Gallery Episode Transcript

"This Mortal Coil" is the tenth episode of the fourth season of Stargate: Atlantis.


When a mysterious drone crashes into Atlantis, Lt. Colonel John Sheppard and his team suspect the Asurans have found them, yet when they investigate, certain people want to stop them from finding the truth. And yet, stranger still, Dr. Elizabeth Weir returns to Atlantis out of nowhere.


McKay going over a diagnostic.

In Atlantis, its Stargate has somehow been mysteriously inoperable for more than a week, around the same time since McKay was "screwing around with it". Dr. Rodney McKay and Dr. Radek Zelenka are working on restoring it. But just as they work, they hear a noise, as if something has crashed into the city. McKay puts the repair of the Gate on hold and investigates. He then discovers a mysterious probe that has somehow arrived undetected. He then notices a scorch mark, as if someone fired a drone weapon to stop it. McKay and Zelenka attempt to determine its origins. Zelenka tells McKay it could take hours, but McKay ignores him and finds something. He sees Zelenka attempting to do something, but stops him. McKay then sees nanite coding for a sec, but then the diagnostic system suddenly crashes, which causes them to lose all their data. Something that McKay suspiciously blames Zelenka for but which he denies. McKay finds out that the probe belongs to the Asurans.

He runs to Lt. Colonel John Sheppard and tells him the Asurans have found them. Zelenka is with them too, but tells them that he did not see anything, and claims he had the same data readings as McKay. He insists that he saw the base code, but as he is about to prove it, they hear an explosion. Major Evan Lorne tells them that the probe self-destructed, meaning their chance of finding any clues to the origins has gone. McKay suspects foul play.

Sheppard then goes to the gym for a sparring session with Ronon Dex. During the session, Ronon says he and Teyla Emmagan has noticed strange behaviors from other people. Sheppard just shrugs this as simple paranoia, due to inactivity from the broken Gate. However, Ronon says he is not paranoid and in the process injures Sheppard. He walks to the infirmary, where he goes to Dr. Jennifer Keller for stitches, but she says he does not need stitches, despite he is bleeding, the bleeding injury is completely gone. Sheppard wonders if he may have been infected with nanites from the probe. Keller hesitantly scans him, but sees no nanites. Sheppard then suspects that the Iratus bug retrovirus he once had in his system two years ago has reared its ugly head again. Sheppard demands a blood test when Keller starts stonewalling him.

Later, Keller and Lorne talk in a secluded place. They thought they had everything handled. Since they are far from learning the "truth", they decide to be careful. Later, Keller gives Sheppard a clean bill of health, but he refuses to ignore the fact that the abrasion happened, so Keller claims that he made a mistake. When Keller leaves, Sheppard suspects something is not right, and begins to feel the same as Teyla and Ronon.

The team wonders what is going on.

They bring McKay in. When Sheppard threatens him with a knife, he tries to run, but is stopped by Ronon and Sheppard cuts his hand with a knife. When it rapidly heals, they know that something much bigger is going on, and it's not just about Sheppard. The entire team is affected. They also believe that several key personnel on the base, including Keller and Lorne, have been acting suspicious and secretive lately. When Sheppard points out his magic healing, McKay accesses the city's medical archive, as all scans are recorded. However, he finds that the data has been erased. In order to confirm their suspicions, Teyla and Sheppard decide to sneak into the infirmary undetected, so McKay hacks into the city's biological sensors to avoid Atlantis personnel. However, as he accesses the life signs, he reads only four. In order to avoid suspicion, Sheppard and Teyla continue anyway, but are noticed by Lorne, Keller and Zelenka.

Meanwhile, McKay picks up a fifth lifesign in one of the piers. McKay and Ronon investigate. Sheppard is under the medical scanner, and Teyla watches the screen. Ronon and McKay go to the area of the lifesigns, and discovers a secret door to the room. There, they see Dr. Elizabeth Weir, who was taken captive by the Asurans a few months ago. They wonder what is going on. At that moment, Keller arrives and tells them this is how they made Weir, and the rest of Sheppard's team. Meanwhile, Teyla and Sheppard confirms their fear; they are infected with nanites. There, they are confronted by Lorne. Sheppard warns Lorne, and even holds his sidearm. Lorne tells him it wouldn't do much good, and tells him to shoot anyway. The bullet causes no effect, meaning they are all Asurans.

Keller tells her group that since McKay was able to tamper with the base code, they are now able to take form of anybody they please, and took form of the Atlantis expedition. McKay knows of their first encounter of the Asurans, and that Keller hasn't been head of medical, and has never even arrived yet, but Dr. Carson Beckett was. Keller explains that she had new information from Dr. Elizabeth Weir, who was latest to be kidnapped and had her mind probed. Even the city is a copy and is on another planet.

The captive duplicate team.

Now in the brig, Weir proves the fact she is nanite manufactured, by cutting her hand, only to see the nanites repairing them. The replicated Atlantis team then realize that they are just test subjects for the Asurans. Teyla wonders why McKay didn't notice the fact they are on another planet, since the stars would determine their location. Unfortunately, there was solid overcast for over a week, ever since the Gate was broken. So they've not had a chance to get, or even notice, their bearings.

The replicate Weir is then taken to Keller. She reveals their true purpose for the team. She informs her that the real Weir was killed several months ago because she was too dangerous. Oberoth gave her nanites to save her life. However, she used her mind and gave the other Asurans an "unhealthy influence", so Oberoth had her terminated. RepliKeller and her team are a part of Niam's faction, a group of Asurans who wish to learn ascension. Most were reprogrammed, but a small group managed to have escaped detection and stole a Zero Point Module to construct the city. They discover that since they're machines, not organic, they need the Human counterparts to study their nature and the existence of a "soul" so they too can finally learn to replicate the process to ascend. And now that Weir's team is made aware of their purpose, they plan to wipe their memories and start again. But the team plan to escape first before they can be subjected to the whole process again.

The city is destroyed.

RepliKeller then confronts them again, and tells them that Oberoth has sent the probe, and that now he has found them, he plans to take them back to the collective. The group refuses, so Oberoth now plans to destroy them. An Aurora-class battleship starts attacking the city. They can't raise shields, because the ZPM has used up too much power in creating the Organic Asurans. The team persuades RepliKeller to let them go rather than let them be just a 'failed experiment', so that they can at least attempt stop Oberoth once and for all. Keller finally succumbs and lets them go. As the city shakes and collapses from the weapon's fire, Keller runs to the control room and gives the team a core drive of a ships' tracking system, which should track every Aurora class ship in the Pegasus Galaxy. The team manage to escape to a cloaked Puddle Jumper. Weir tells Keller to come with them. However, she says she may be tracked by Oberoth and would only be a liability, insisting they leave without her. Weir reluctantly leaves her behind. The team escape, while the city is destroyed (matching the same vision Colonel Samantha Carter received some time before).

The Jumper cloaks and chases after the Aurora class ship and hitches a ride as it jumps into Hyperspace, thinking the ship will go to Asuras, which it does. There, McKay notices the ships they destroyed have been rebuilt, but with even far more being built since. They land on the planet and steal a ship, which they take to an outpost on M34-227.

Meanwhile, back on the real Atlantis, Dr. Rodney McKay is working on the Stargate, when Lt. Colonel John Sheppard receives a transmission from an off-world base on M34-227. Major Jordan introduces them to a familiar face. The team are first shocked, then amazed, relieved and elated to see Weir alive and well. She tells them that she is not the real Weir and that they must meet each other, as they have a way to stop the Asurans. Both teams meet, and are a little suspicious when Sheppard's team has a duplicate copy of themselves. There, the duplicate McKay presents the real team the core drive, which should track every Asuran ship in the galaxy. While the McKays work on the base, since it is a security risk to send their copies to Atlantis, the real Sheppard wants to know where the real Weir is.

There, the duplicate Weir sadly informs Sheppard that the real Weir is most likely killed. Ronon Dex and Teyla Emmagan are also mistrustful of the replicates. Meanwhile, their duplicate selves are talking about their real selves. Despite Teyla telling them that since he's a duplicate, he feels himself as a lesser, but with the nanites, can go into more battles with the Wraith, where the nanites will repair him if he's injured. However, the duplicate Teyla tells him that the nanites can't heal him forever. The two McKays however couldn't be happier, getting along like a house on fire, both relishing the opportunity to have each other's superior mind for company and better combined problem solving - which they go off to do immediately...

An Asuran ship guarding the gate.

Sheppard and Weir talk more, when an Asuran cruiser arrives and begins attacking the camp. Weir thinks that their ship had a system, which the rest were able to track. Worse, there's another ship guarding the Gate and will take out anything they see attempting to leave through it. With the gate cut off by the Asuran ship, they need to stage a diversion if they hope to escape. The replicate Atlantis team plan the diversion, to prove themselves how Human they really are. They take a Jumper and use it to distract the warships. The two chase after them, as the Stargate is dialed to Atlantis.

Meanwhile, the Jumper attempts to cloak, when the Jumper gets shot down. The Asuran patrols scout the area and find the crashed Jumper. They enter to see the team seemingly dead, apart from Sheppard, who gets healed by nanites and confronts the Asuran team, much to their surprise as they observe his wounds healing right before them. He tells them "Yeah, we tricked you. But don't feel so bad. After all, we almost had ourselves convinced" before he is shot and killed. Their selfless and heroic sacrifice has allowed the real Atlantis team to escape successfully.

McKay and Sheppard discovers how many ships are around.

Back on Atlantis, Sheppard finally decides to remove Weir's personal effects from the city and return them to Earth, now that she is confirmed dead. Meanwhile, McKay works on the core drive for hours, trying to forget about the loss of Weir, stating it's like Carson all over again. Zelenka attempts to talk to him, only to be hushed and sent away, telling him maybe later but not now, before regretting his abruptness and thanking Zelenka for trying. Several hours later, Sheppard enters the lab, where McKay finally manages to get the Aurora-class warship tracker working. At first, they only see a few dots across the galaxy, and are pleased that it doesn't look too critical. Until he notices more popping up, and then even more again. Eventually, they are shocked to discover around 30-40 Aurora class ships lighting up the whole screen. During the fade-out, still more beeps are heard with McKay's horror clearly heard as he ends with an : "Oh, crap!..."


Appearances for This Mortal Coil





Sentient Species



Notable quotes

Sheppard: All right. Do we know what the problem is?
McKay: Yeah, the Gate's not working.
Sheppard: I think we figured that much last week when you broke it.
McKay: I did not break the Gate.
Sheppard: Oh, so it just happened to stop working around the same time you were screwing around with it.
McKay: I wasn't screwing around with it! I was running a streamlining programme designed to boost its operating efficiency.
Sheppard: Yeah, well, good job.

Sheppard: Any injuries?
Marine: No sir.
McKay: Oh thank god it hit the reading library or someone could have really got hurt.

Sheppard: Great, the last time I came face to face with myself, I ended up kicking my own ass.

Duplicate McKay: (About real McKay) Oh this is great. Finally someone who I can have 100% confidence in; I cannot tell you how much I am looking forward to working with you! And this is just the beginning but humanity is about to benefit from one of the greatest living scientific minds... x2!
McKay: Can you imagine?
Duplicate Sheppard: I'm trying not to.
(Sheppard smiles)

Duplicate Sheppard: Hold on a second. Where do you plan to do this? We're too much of a security risk to go to Atlantis.
Sheppard: He's... I've got a point.

McKay: Huh...If this works, we should be able to track every Aurora Class Replicator ship in the galaxy in real time.
(screen shows half a dozen ships)
McKay: (relieved) That's not so bad. I guess the Wraith have really taken a toll.
(more ships appear on the screen)
McKay: On.. the other hand, they might have built even more.
(a lot more ships appear)
McKay: ... a lot more...
(sounds of more ships appearing)
McKay: Oh, crap!


Main Characters

Guest Stars


  • Despite being the mid-season finale, the episode does not end with the traditional "To Be Continued..." tag.
To sleep: perchance to dream: ay, there's the rub;
For in that sleep of death what dreams may come
When we have shuffled off this mortal coil,
Must give us pause: there's the respect
That makes calamity of so long life;
[...] Soft you now!
The fair Ophelia! Nymph, in thy orisons
Be all my sins remember'd.
  • Dr. Rodney McKay's reaction to his duplicate is very different to his treatment of his alternate self in "McKay and Mrs. Miller", in which he was vehemently opposed to keeping the other McKay around and insisted that "there is only one McKay" though he may have just been threatened by Rod's charm and likability. The real McKay could also be intrigued by the duplicate McKay because he is an identical copy, as opposed to an alternate reality McKay, where decisions made during his life were slightly different.
  • This is the first episode to make direct reference to the new Atlantis uniforms, when McKay and his duplicate talk about how they are better than the old ones. This is an in-joke referencing how much David Hewlett lobbied for the new uniforms after finding the old ones uncomfortable.


  • At roughly 38:40, Ronon Dex appears to rotate the surrounding tree.
  • When the original and the duplicate team meet on M34-227, the two McKays are very clearly not looking at each other.
  • Despite the duplicate team stealing a Replicator ship, using it to fight back against the Asuran cruisers is not discussed. While they can't use it to travel back to Atlantis due to its apparent tracking device, they could at least use it to fight back or travel to another planet where they can safely use the Stargate.
  • At around 41:32 there's a shot of Atlantis at night with the two visible moons present along with a hazy/overcast sky, and while the smaller moon along with a star is visible in a break in the clouds the larger moon appears to be in front of the clouds instead of behind them.
  • At around 38:37, the Dial Home Device shown on M34-227 is a Milky Way Galaxy style DHD, not Pegasus Galaxy style. The same appears to be true with the gate, despite it having blue chevrons. However, it is not possible to see it clearly, so this may be incorrect. Also, the 3rd and 4th chevrons are not shown, and do not appear to have locked, either.
  • Duplicate Weir was aware that the Asurans had begun to annihilate human worlds. It is possible this information was revealed to her by Niam's faction, but that conversation is not shown, and Asuran Keller appeared to be surprised when it was mentioned.

Other languages

  • Hungarian: Halandó porhüvely (Mortal Corpus)
  • German: Die Mühsal des Sterblichen (The Toil of Mortal)
  • French: Double Collision (Double Collision)

External links

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