the story: The Federation mends fences with the Klingons as the Dominion threat comes into focus.
what it's all about: Basically, "By Inferno's Light" completes the reclamation of what Deep Space Nine was originally about with what the studio attempted to make it with the insertion of Klingons into the fourth season in an ill-fated effort to ramp up its popularity and/or accessibility. With Dukat finally assuming full authority over the Cardassians and completing his journey to becoming the definitive Cardassian in the process (it's shocking to think it really did take this long to achieve, with considerable work done during the third and fourth seasons to set it up), the original premise of the series, that Starfleet was coming to Bajor to help it recover from Cardassian oppression, becomes an integral component of the Dominion arc that had at times seemed sidelined by the Klingons.
Yet, at no point in franchise lore had the Klingons truly become such ready allies with the Federation as they do by the end of this episode. Picard seemed to have special sway in Next Generation, but that translated to one man, a limited scope that kept relations at a distance. Gowron, the Klingon leader whose debut in Next Generation helped set the tone of the warrior culture moving forward, passes the torch to Martok here, Martok whose earlier appearances couldn't really give an indication of his later significance.
That begins to change in "Inferno." His relationship with Worf deepens as they grow to depend on each other in a Dominion prison camp. This is also, primarily, Worf's best Deep Space Nine moment, by the way. He becomes forced to compete in a series of fights with Jem'Hadar soldiers, persisting even when he begins to break down because of his famous pride. He's never been pushed like this before, never been forced to demonstrate just how far he's willing to go. As a Klingon, he'd always represented his people well, but he was more often than not constrained by the oath he took to Starfleet. Too often, even in Deep Space Nine, his Klingon loyalties ended up seeming like a weakness. There's no such hesitation here. His prowess in combat, only hinted at elsewhere, becomes as much a focus of his arc in the episode as his legendary resolve. While Martok is there to support him, this is totally Worf's show.
There's also Garak finding out that Dukat has singled him out in his efforts to reclaim Cardassian honor, but by making it clear he thinks Garak has no honor, and no place in the new Cardassia. This is much as Garak had experienced in recent years anyway, but he also went to extreme lengths, in this two-part episode, to prove his loyalty to his people. Shows what integrity gets you. Somewhat surprising is that for the first and only time, he and Bashir share an adventure together ("Our Man Bashir" doesn't count), but it's not an experience that's particularly relevant to their bond. Increasingly, Bashir moves off in his own direction (see the next episode, "Doctor Bashir, I Presume?" as well as "Inquisition," which ironically integrates him into the world of spies, which he'd only previously known about from his suspicions about Garak's past).
This is a big, big moment in the series, where the war becomes positively inevitable. It ends somewhat tidily, but by the end of the season, everyone knows such developments won't be possible anymore, which makes this somewhat the last of the happy endings in Deep Space Nine...
- franchise - A big moment in Federation/Klingon relations.
- series - A big moment in Dominion relations. And Cardassian relations!
- character - Arguably Worf's finest moment.
- essential - This is self-explanatory, given the above statements.
Andrew Robinson (Garak)
Marc Alaimo (Dukat)
Melanie Smith (Ziyal)
J.G. Hertzler (Martok)
Robert O'Reilly (Gowron)