my current rhaenicent s3 predictions based on released stills, trailers, and leaks:
alicent returns to king's landing and learns that aegon is missing. she convinces aemond to leave the city with vhagar and then, knowing rhaenyra likely won't believe that aegon's escape had nothing to do with her, tries to flee the city with helaena instead of upholding her deal with rhaenyra. rhaenyra takes king's landing similarly to how it plays out in fire & blood (daemon-loyal gold cloaks turning on their brothers, etc). alicent and helaena are captured by rhaenyra's men before they can escape and are brought before rhaenyra, leading to a brief queen in chains era for alicent. there are some tense intimate conversations with rhaenyra during her imprisonment that lead to rhaenyra giving alicent more freedom and alicent eventually acting as rhaenyra's unofficial advisor as she becomes distrustful of her actual council.
