This episode is part 1 of 2; it is followed by "Small Victories".

"Nemesis" is the twenty-second episode of the third season of Stargate SG-1.


Thor's ship is above Earth and is overrun with an Asgard's nemesis that is even more powerful than the Goa'uld: the Replicators. Colonel Jack O'Neill and SG-1 are beamed aboard to find out a way to stop them before they can infest Earth.


Dr. Daniel Jackson is resting in the infirmary because his appendix has been removed. Thus, the rest of SG-1 gets leave time. Teal'c is off world visiting his son and Colonel Jack O'Neill tries to invite Major Samantha Carter to a fishing trip in Minnesota. Carter follows O'Neill halfway through the base to wish him a good time when he disappears in a flash of light. O'Neill finds himself on an Asgard ship orbiting Earth. He encounters the Replicators who have infested the Biliskner, Thor's ship. Thor is on board and explains that the Replicators took over his ship. The navicomputer contained the coordinates for Earth and they set a course for it. Thor is also dying but has made recordings about the technical specifications of the Biliskner so that O'Neill might find a way to stop the Replicators from landing on Earth. Thor also disabled the outbound transporter beams to prevent the Replicators from escaping.

Back on Earth, Stargate Command has been trying to locate the ship in orbit but the Asgard cloaking device prevents such detection. O'Neill sends a real-time holographic image into the SGC conference room where Major General George S. Hammond, Carter and Teal'c were discussing the situation. O'Neill needs 10 pounds of PBX, a Franchi SPAS-12 shotgun, USAS-12 automatic shotgun shotgun, and a BF-8 at the foot of the Stargate.

O'Neill explains that he needs the ordnance to destroy the ship. He also explains that no one is going to get off the ship and orders Carter and Teal'c not to come on board.

Nemesis 3

Teal'c and Sam arriving on the ship.

However Hammond overrules the order and sends them anyway much to Jack's anger. Carter explains that a shuttle is ready to launch and can reach them in a matter of hours as long as they have the correct coordinates.

After more discussion with Thor, SG-1 must try to retake the bridge and crash the ship in the atmosphere to burn it up. However, when Teal'c and O'Neill reach the bridge it is completely overrun with Replicators and there is no chance of even reaching the navicomputer let alone putting in a new course. They must make a new plan.

Carter and Thor then suggest putting an elementary Naquadah enhanced bomb (BF-8) on the deceleration drive and detonate it when the ship enters the atmosphere. SG-1 has to place it on the outside of the hull, as Thor explained that the ship's internal systems included explosion suppressors. Teal'c volunteers to place the bomb because his Goa'uld symbiote will protect him from possible radiation around the ship.

As Teal'c leaves the airlock, a small and unseen amount of partially melted metal drops onto Teal'c's air tank and slowly starts eating away. Teal'c plants the bomb and returns to the airlock but the outer door is shut and won't open. Carter tries to override but the airlock has been tampered with by the Replicators. At that moment Teal'c's tank blows and he is losing oxygen fast. Carter tells O'Neill that she can beam Teal'c aboard but only if he is far enough away from the ship. Teal'c weakly pushes off and Carter beams him aboard after an excruciatingly long minute. Thor's vitals crash and Carter activates the stasis pod he's in to preserve his life.

With the bomb placed, all SG-1 has to do is wait for the right time to detonate it. They now have to figure out how to get off the ship. SG-1 transports the Alpha gate, the gate at Stargate Command, on board with Hammond later ordering that the Beta gate be brought out of storage and set up.

Back on the ship, SG-1 plan to gate to P3X-234 and then home to the Beta gate. However the energy output of the transporter has attracted the Replicators to the Gate. Teal'c activates the gate manually while O'Neill and Carter cover him from a huge swarm of Replicators.

O'Neill blows the bomb and the ship tumbles out of control and crashes in the Pacific Ocean.

Nemesis 1

A Replicator standing on the edge of Thor's ship in the Pacific.

However while the ship sinks, one surviving Replicator crawls to the surface, revealing that the Replicator threat lives on.



Appearances for Nemesis





Sentient Species




Notable quotes[]

(O'Neill activates a video message from Thor)
Thor: Under my command, the Biliskner was called into battle against an enemy we have named "Replicators." During the battle, this ship became infested by the technology. The Replicators accessed the computer which contained information about your planet and plotted a course here. The crew was transported off the ship. I destroyed the outbound transporter technology to prevent the Replicators from escaping and remained in the hopes of stopping the Biliskner from reaching Earth. If you are watching this recording, then I have failed. And I have also likely doomed you to certain death.

Hammond: Welcome back, Major.
Davis: General, I wish it wasn't always under such unusual circumstances.

Thor: The replicators were brought upon an Asgard ship, for study, before the danger could be fully comprehended.
O'Neill: We do that all the time, kinda expected more of you guys.

(As Teal'c prepares to step out of the airlock.)
O'Neill: Say something.
Teal'c: One small step for Jaffa.
O'Neill: Very nice.

Jackson: Sir, I know there's no reason for me to be here but I just, I feel like I should be here. That's not totally true. I feel like actually I should be up there with them.
Hammond: Now you know how I feel most of the time.

Teal'c: Thor was correct, we are going to die.
O'Neill: Ah Teal'c come on, we have been in worse situations before.
Carter: No sir, we haven't.
O'Neill: We haven't?

Davis: I'm sure you were right, Dr. Jackson. The point of commandeering the Stargate had to be an escape.
Jackson: I just hope they made it out in time.


Main Characters

Guest Stars


  • Dr. Daniel Jackson's Appendicitis reflected Michael Shanks' real-world condition; it was written into the script at the last minute because the writers needed to drastically reduce Shanks's role to allow for his recovery. Shanks's scenes in the episode were actually shot a week after filming of the episode was completed although Shanks did appear in the episode, voicing Thor, the Supreme Commander of the Asgard Fleet.
  • This episode is the first to be shot completely in 35 mm. Previous episodes were all filmed in 16 mm (except the effect shots). All future episodes would be shot in 35 mm until the show switched to HD starting with "New Order, Part 1".
  • When preparing for a spacewalk, Teal'c says "One small step for Jaffa". This is a reference to Neil Armstrong's quote "One small step for man" when he first stepped onto the Moon in 1969.
  • The weapon Major Samantha Carter carries in this episode may appear to be an M4 Carbine, but it is in fact a member of the Colt CAR-15 Commando family, as indicated by the short 11.5-inch barrel and 4.5-inch flash hider. Interestingly, the gun also very clearly has a forward assist on the receiver but no case deflector, indicating it is not a US Air Force GAU-5A/A (which has no forward assist or case deflector) or the more modern M4 Commando (forward assist and case deflector), but rather a US Army XM177E2, an odd choice of weapon for an Air Force officer.
  • Starting with this episode, the main title sequence on the DVDs is the original sequence of the Sphinx instead of the montage of clips used for syndication airing as used on the previous DVD releases. This sequence will be used for all episodes going forward until the season six premiere episode, "Redemption, Part 1". The opening sequence would again be changed in the Season 6 episode, "Descent".
  • This episode reveals that even after being disconnected, the Stargate holds enough power for one dial out.
Nemesis 2

Martin Wood's cameo.


  • When Thor is talking to SG-1 about the Biliskner he states that the "heat from the friction would cause the ship to burn up." While aerodynamic friction does produce some heat, the vast majority of heat generated during a reentry from orbit is due to the compression of air into plasma.


Other languages[]

  • French: Némésis (Nemesis)
  • Italian: Nemesi (Nemesis)
  • Spanish: Justo Castigo (Fair Punishment)
  • Czech: Nemesis (Nemesis)
  • Hungarian: Nemezis (Nemesis)
  • German: Nemesis, Teil 1 (Nemesis, Part 1)

Links and navigation[]

Smallwikipedialogo This page uses content from Wikipedia. The original article was at Nemesis (Stargate SG-1). The list of authors can be seen in the page history. As with SGCommand, the text of Wikipedia is available under the GNU Free Documentation License.
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