The little birds Varys left when he fled King’s Landing are now in the hands of Qyburn, and all along his little birds were a gaggle of mistreated poor kids. He received their “whispers” through sweets and kindness, of which Qyburn can provide and at least fake, respectively. The dormant volcano that is Cersei’s vengeance is stirring, and she commands Qyburn to get the whispers of little birds from all over Westeros: “If someone is laughing at the queen who walked naked through the streets covered in shit, I want to hear. I want to know who they are. I want to know where they are.”
Jaime’s still preoccupied with taking down the High Sparrow by using Zombie Mountain’s mute strength (even though he unwisely took a shot at the mutant’s intelligence level.) Cersei says the Mountain can’t face the whole of the Faith Militant alone, though he won’t have to, as “he’ll only have to face one.” This prompts Jaime to ask, “Has the Faith leveled official charges yet?” And “not yet” is the response. The show hasn’t referenced whatever it is they’re discussing, though I can only imagine it has something to do with whatever whispers the little birds provided them before they scarfed down their candied plums.
Feeling empowered by the cheap task of weaseling information out of the underprivileged youth of King’s Landing, Cersei and Jaime push in on the Small Council meeting using Zombie Mountain as a barrier. Fortunately for Maester Pycelle and his nervous sphincter, the reanimated Ser Gregor doesn’t quite have the brutishness he once did. So even though he insulted the monster and Uncle Kevan and the Tyrells abandon the meeting due to their uninvited guests, the Mountain just stood in silence. He can’t go smashing everyone’s head in, just as Kevan suggests.
While the Small Council was deliberating on what to do about the queen (decidedly not Cersei, thank you Lady Olenna!) still locked up in the sept, Tommen took it upon himself to finally confront the High Sparrow. The High Sparrow refuses to allow Cersei to see Myrcella’s resting place because she still hasn’t atoned for all of her sins. Listen, this bitch is kind of the worst, but honestly, what more does she need to do?! Tommen echoes this sentiment several times, but doesn’t get though to his elderly target. The High Sparrow makes friends as fast as Cersei makes enemies with all his anecdotes and sympathetic gripes about his knees. Whatever vitriol Tommen had before he went to the sept evaporates, and before he knows it he’s having a pleasant chat about how “the Crown and the Faith are the twin pillars of the world.”