A review of tonight's "Game of Thrones" coming up just as soon as there's a word for cousin-killing...

"Don't worry about your death. Worry about your life. Take charge of your life, for as long as it lasts." -Littlefinger

When you have an episode called "The Mountain and the Viper," and you go in knowing the promise and the stakes of that title, and then the episode waits until the last five minutes or so to give you the match in question — and waits until only five minutes before that to provide a glimpse of the character we love whose future rides on the match's outcome — it can feel in a way like a championship fight with an extremely long undercard, where the promoter has placed every bum, tomato can and loser in his stable into the lineup because he knows the crowd will suffer through them in order to get to the main event.

Benioff and Weiss have very strategically inserted each of Ramsay Snow/Bolton's appearance so far this season, for instance, into episodes where they knew that all anyone would be talking about was the climax (first the wedding/assassination, then Tyrion's trial, and now the trial by combat), so of course we got more of his mind games with Theon/Reek, more blood and flaying, and all of House Bolton heading for the ruins of Winterfell to try to make it cozy in spite of the thorough job Ramsay did trashing it two seasons ago. And we get other assorted bits of lower-level business, like Arya and the Hound finally making it to the Vale (albeit perhaps three days too late to do much good), the wildlings getting ever-closer to Castle Black, and Grey Worm flirting with Missandei despite missing his stones (and possibly his pillar), along with slightly bigger plot developments like Dany exiling Jorah for spying on her back in season 1, and Sansa throwing in her lot with Littlefinger, and against the likely doomed Robin Arryn. I'm frankly stunned Benioff and Weiss didn't try giving us another Stannis monologue about the pain of being denied his birthright, simply because they knew we'd sit through virtually anything to get to that fight.

But I'll let it slide, for a couple of reasons:

First, while the undercard had some duds, it also offered plenty of terrific entertainment in its own right, particularly whenever one of the Stark sisters was involved.

And second? The fight was really worth the wait.

We'll hit the other action in the bullet points, but the episode kicked into a higher gear as soon as it got to King's Landing, first with Tyrion's story about their slow-witted cousin, then with the duel itself. The scene between the brothers was excellent, as any Tyrion-Jaime conversation tends to be, and specifically fascinating because of the seeming randomness of the cousin story. The tale is a reminder not only that Tyrion is no saint — he mocked the poor kid just so he could feel normal for once, and still laughs now as he imitates his brain-damaged speech — but that he is a very different creature from the rest of his family for reasons that go well beyond his stature. Jaime is baffled that Tyrion would be so obsessed with the ritualistic slaughter of beetles in a world where so many humans are brutally killed each and every day, but Tyrion doesn't think like Jaime, or Cersei, or Tywin, or anyone else. To him, the beetles weren't simply a measure of his cousin's madness, but a puzzle to be unlocked — and, in the process, explaining not only something practical that young Tyrion witnessed every day, but some larger mystery of the universe into which he was born so cruelly, and from which so many of those people his brother mentions exit so violently. It means nothing, and yet the randomness of it — and the fact that Tyrion knows he will go to his grave, whether in days or in many years, not knowing the answer — feels like exactly what would be occupying his mind as he waits for his life to be decided by the skill and wisdom of other men. That he cared so much about the beetles isn't a reason Tyrion Lannister should live or die, but the show's universe is vastly more interesting with such a man in it...

...which is why I assumed without any real hesitation that Oberyn would score the huge upset victory over the Mountain and secure Tyrion's life and freedom to the dismay of his father and sister. And for a while, that's exactly how the fight played out, with the big bully unprepared for the quickness, acrobatics and sheer ruthlessness of his smaller opponent. But then the Viper got a little too caught up in his Inigo Montoya routine, repeating his sister's name over and over, dancing around and taking pleasure in prolonging his foe's agony rather than delivering the killing blow. This was, of course, a fatal mistake — and a pretty gruesome one, too, as the Mountain crushed Oberyn's skull with his bare hands (and let's give all the Emmys in the world to both the sound and makeup teams for the job in bringing that moment to stomach-churning life), putting smiles back on Tywin and Cersei's faces and crushing the hopes of both Tyrion and his fans in the process.

It's a savage turn of events, and yet not an unfair one. Though Pedro Pascal's done well with his opportunities this season, Oberyn ultimately never developed into an important enough character to really justify him saving Tyrion's life in this way; his victory wouldn't have felt like a deus ex machina, but nor would it have felt entirely organic to the story, especially after Tyrion was already saved once by a previously obscure combatant. If Tyrion is somehow going to survive his current dire circumstances, I would hope it would be in a different way — and/or with him playing a more active role in his own salvation. And if he has run out of chances due to the Viper's preening? Well... I got over Ned Stark, though I was feeling much less affectionate towards him and his stupid head than I am to Tyrion at this point.

We'll see what fate has in store for the Imp. As for the Viper, it's his own fault for dancing around and not finishing the job. That was tough to watch, but also exciting as hell.

Some other thoughts:

Alan Sepinwall has been reviewing television since the mid-'90s, first for Tony Soprano's hometown paper, The Star-Ledger, and now for HitFix. His new book, "TV (The Book)" about the 100 greatest shows of all time, is available now. He can be reached at sepinwall@hitfix.com