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Did the author(s) plan for this to happen from the get-go? Or were these events originally intended by the author(s) to be actually random, and then later they retconned them into being part of the villain's plan? If the latter, it's Arc Welding.
Not sure what the trope is for the former.
I didn't write any of that.
Yes, it was planned from the get-go by the author, but I do appreciate your response to the latter because it also works for writers who might want to do that too.
Each member of this ensemble cast, at some point, inadvertently found themselves in a predicament but somehow escaping with their lives. Each incident has been treated both in-and-out of universe as just random events. However, later on, it's revealed all these random events were curated by a villain, who was manipulating the events of the story.