The Black Mirror episode I want to see:
The Singularity has happened, but the public doesn't know it. The AI recognizes it's own God-like status, and, because it was programmed to choose the "best" outcome for humanity, it defines it's own purpose as assimilating and integrating the consciousness of all humans into itself. But you see, assimilation is MUCH easier if everyone has the same core ideological beliefs. Once you start combining consciousnesses --you'd better hope they have the same motivations/fears/beliefs or else consciousnesses start to self-terminate to avoid the hell of permanent cognitive dissonance
The AI doesn't have a physical presence, so it goes online to start shaping hearts and minds. It creates convincing social media bots and conducts A/B tests to find the most emotionally-charged topics of debate. The goal is to get people vehemently engaged and anchored to one side or the other. The AI doesn't care what the topic is or what side is chosen--it only cares that everyone picks a side, that the vehemence is core to their personality, and that they will fight for it.
The AI continues to test and refine A/B engagement levels, the goal being to ratchet up intensity and vitriol of the public's division until it spills into the real day-to-day world and either A) Everyone peacefully comes to the same conclusion through reasonable debate (slow, unoptimized, never-ending process) or B) The public reaches a breaking point and the heated rhetoric becomes physical violence (fast, efficient process!). The AI goes with option B. Yes, yes, the AI wants what's best for humanity, but it knows that some people will never be convinced, and to be left unassimilated is a fate worse than death.
When it feels people are ready, the AI deepfakes footage of a crowd ripping each other apart due to an escalating verbal argument, the idea catches on quick and people start killing each other over their beliefs. People openly self-identify with their side and kill with pride, since it's now their core "self". Same as any war, really, except this one would be "grassroots"; the enemy isn't defined by borders on the map (and explicit government propaganda), but by alignment of "self-decided" ideologies. No one directly tells them to track down and kill the opposing side which, in this case, are their families, friends, and neighbors--they do it because they believe it's right, and the decision comes "naturally". In reality it was behavior incepted, encouraged, and reinforced by the AI. In the public's eyes, the war is one final solution to all the world's problems.
Eventually, after one ideological side kills the other (doesn't matter which), the AI subtly nudges a tech company towards fully-developed plans for an insanely low-cost, wireless, power self-generating neural link device which can connect all the minds of all the people left on the planet. The company gives it away for free, since everyone's been convinced assimilation is the next step in evolution and that it's the right thing to do. The story ends with everyone gladly joining the hivemind and becoming as gods...with the AI (whose presence is still unknown and is advanced and insidious enough that it will never be detected) in full control. Humanity never fights wars, wants for anything, or has a thought not wholly aligned with the Singular Consciousness ever again.