"That thing won't stop until it finds her."
— Jacob Carter
The Alpha Site is attacked by Anubis's forces while Carter and her father are there working on a prototype weapon to use against the Kull warriors; the base is destroyed by the self-destruct, but Carter is still missing, severely injured and on the run with a Kull warrior determined to hunt her down. Meanwhile, the Earth-Tok'ra-Jaffa alliance begins to fall apart when it becomes clear that there's been a security breach regarding the site's location and all parties start accusing the others of being responsible.
"Death Knell" provides examples of the following tropes:
- Beauty Is Never Tarnished: Averted; Carter is beat up pretty badly after the initial destruction of the Alpha Site and spends most of the episode with her face bloodied and covered in dirt.
- Big Damn Heroes: Teal'c and O'Neill show up just as the Kull warrior is about to finish Carter off for good.
- Bittersweet Ending: The SGC successfully completes a working anti-Kull warrior weapon. But the Alpha Site is destroyed and their alliances with the Tok'ra and Free Jaffa fall apart as the conflict with Anubis intensifies.
- But Now I Must Go: The Tok'ra and the free Jaffa both leave the alliance at the end of the episode, albeit for different reasons; the Tok'ra don't want to put any more of their operatives at risk by disclosing all of their activities to Earth, while the Jaffa feel that they need to establish themselves as an independent party after millennia of servitude. Jacob specifically makes it a point to visit Carter as she's recovering in the infirmary and tell her that he probably won't be coming back for a while.
- Call-Back:
- The Stargate on the Alpha Site gets toppled on its side after being hit by an al'kesh and carves out a crater beneath it when it's dialed, similar to what happens in "A Hundred Days".
- At one point O'Neill gives the line "we'll jump off that bridge when we come to it."
- Chekhov's Gun: Carter uses the missile from the downed UAV to try and take out the Kull warrior. Not that it does much good.
- Conflicting Loyalty: Delek accuses Jacob/Selmak of being torn between his loyalties to the Tok'ra and his ties to Earth, stating that he's fallen out of favor with much of the Council as a result.
- Continuity Nod:
- It's mentioned that the Alpha Site has been moved since Anubis could have learned its old location from probing Jonas's mind.
- The Carters have been able to develop a prototype weapon to use against the Kull warriors after studying the Telchak device.
- M'Zel states that all of the Jaffa formerly loyal to Heru'ur were forced to serve Apophis after the events of "The Serpent's Venom".
- Delek claims that all Tok'ra operatives has a means of killing themselves if they're captured.
- Selmak tells M'Zel that countless millions of Tok'ra symbiotes died in the development of the tretonin which has allowed the Jaffa freedom from their dependence on the Goa'uld.
- Hammond comments to M'Zel that Anubis doesn't need to torture prisoners to get information, he has the means to simply download the information out of their head.
- Deader than Dead: Delek states that in the event a Tok'ra operative is captured, they have a means of killing themselves in such a way that not even a sarcophagus would be able to bring them back.
- Destructive Saviour: Delek accuses the team of being this, claiming that in the time the Tok'ra have been allied with Earth, they have lost more operatives than ever before. Jacob reluctantly admits that he has a point.
- Determinator: Hammond describes Carter as such.Hammond: I don't know anyone tougher or more resourceful. She'll find a way out of this.
- Divided We Fall: Selmak cites this trope to try and convince the alliance to stay together.Selmak: More system lords have fallen in the past seven years than in the seven hundred years previous.M'Zel: It is true that together we are strong.Selmak: And divided, we will die.
- Does This Remind You of Anything?: Jacob sheepishly admitting that he gave up coffee because Selmak doesn't like it is somewhat reminiscent of a husband making compromises for a nagging wife.
- Dying Race: This is given as one of the reasons why the Tok'ra feel that they can no longer be part of the alliance, since their operatives can't be replaced if they die in battle in the same way that the humans and the Jaffa can.
- Going Down with the Ship: It's briefly mentioned that the commander of the Alpha Site stayed after setting the self destruct while ordering the rest of the personnel to evacuate.
- Heroic Sacrifice: Played for black comedy. Jacob was forced to give up Coffee because Selmak does not care for it.
- Hope Spot: Carter has one when she thinks she's finally succeeded in killing the Kull warrior with the UAV missile, only for it to get back up from the rubble moments later.
- Humanity Is Infectious: Delek claims that Selmak has been influenced by Jacob to the extent that he is now more sympathetic to the Tau'ri than the Tok'ra. By comparison, most Tok'ra hosts are humans from worlds conquered by the Goa'uld, so the symbiote generally tends to be the dominant one despite an otherwise equal relationship.
- Imperial Stormtrooper Marksmanship Academy: The Kull warrior has a clear shot at Carter at several points throughout the episode and somehow manages to miss her every time.
- Implacable Man: See the page quote. The drone keeps coming at Carter no matter what she throws at it, and would have kept on doing so indefinitely had O'Neill not eventually taken it out with the prototype weapon.
- Jerkass Has a Point: There's no denying that Delek is an arrogant S.O.B., but he does have a point in reminding Hammond that it's not exactly unheard of for allies to practice less-than-full disclosure with each other.
- Locked Out of the Loop: Jacob/Selmak realizes that he's been deliberately kept in the dark about several Tok'ra operations due to certain members of the council beginning to question his loyalties.
- No One Gets Left Behind: As soon as it's become apparent that the Alpha Site has been compromised, O'Neill, Daniel and Teal'c immediately request permission to head out and search for survivors.
- Not So Invincible Afterall:
- The destruction of the Alpha Site is enough to kill some of the Kull warriors. As Jacob points out, they can't ignore physics and enough kinetic energy will be fatal. Unfortunately, "enough" is above the threshold of being hit by an air-to-surface missile.
- More significantly, the (handheld) weapon that can kill them is finally completed.
- Only Sane Man: Hammond makes it clear that he considers Jacob to be this and asks for his help in trying to keep the alliance together.
- Open Mouth, Insert Foot: Col. Reynolds has a moment of this when the search party arrives at the Alpha Site, apparently forgetting that Carter is among those missing.Reynolds: (casually) Who could have survived this?(O'Neill glares at him silently for several seconds)
- Race Against the Clock: The development of the Kull Disruptor. As Jacob grimly notes, Anubis is kicking the crap out of all the other System Lords with his Warriors and they're running out of time to produce a working prototype.
- Rage Breaking Point: After much political wrangling, Daniel finally loses his temper when the Tok'ra and the Jaffa both announce their intentions to leave the alliance.
- Riddle for the Ages: It is never established if Anubis learned the location of the Alpha Site from the Jaffa or the Tok'ra (or even both sources). Jacob muses they'll probably never learn.
- Scarily Competent Tracker: Teal'c is able to determine that a pair of boot prints belong to Carter from the fact that their depth is consistent with somebody of her size.
- Self-Destruct Mechanism: The self-destruct at the Alpha Site is triggered when it's attacked by Anubis's forces, to prevent any sensitive materials from falling into enemy hands.
- So Proud of You: Jacob tells Carter this before he leaves at the end of the episode.
- Surprisingly Realistic Outcome:
- Recovering Telchak's device back in "Evolution" does not mean the SGC and Tok'ra now have an instant anti-Kull Warrior weapon. It's taking time to experiment and refine a working prototype.
- Anubis probing Jonas Quinn's mind during "Homecoming" granted him access to sensitive SGC intel that the Goa'uld didn't previously have. Among the compromised data was the secret location of the Alpha Site, meaning the SGC had no choice but to abandon the base before Anubis could launch an attack.
- Tranquil Fury: Jacob and Selmak are both pissed when they realize the Tok'ra leadership no longer trusts them and have locked both of them out of the loop.
- We ARE Struggling Together: The Earth-Tok'ra-Jaffa alliance basically falls apart in this episode, with none of the parties involved able to fully trust any of the others.
