And yes this is not an unusual or an unfamiliar thing in real life - we have all seen it in TV, and occasionally been annoyed by it (stop teasing! Just show us the next episode when you show us the next episode!) - but I don't think I have ever had it happen to me while I was dreaming.
I no longer remember the dream I was having at the time in sufficient detail to know whether or not it is going to "follow up" in the manner that seemed to be promised. I mean, I've had "serial dreams" before - the kind where some story simply picked up where I had left off. But this doesn't feel like one of those. It would have been interesting to see if my brain was showing me "trailers", though. Just saying.