As a cadet sets out to solve an ancient Starfleet mystery, she embarks on a journey of self-discovery and learns the value of forging her own path. Meanwhile, Nahla agrees to help a fellow chancellor with an elaborate alien ritual.

I have a strong suspicion that this shot from one of the early trailers wasn’t a throwaway easter egg as many of us assumed:

Cadet SAM examining a wall panel that says, "Contronting the unexplainable. The fate of Benjamin Sisko, Emissary of the Prophets. Captain Sisko’s Fate: Did he die in the Fire Caves of Bajor? Did he live on in the Celestial Temple?