Speaking of Agent Coulson, he's featured incredibly briefly in the trailer, shown sporting a healthy head of hair like fans have never seen before (this being set in the past, after all).
The size of his role remains totally unknown, though: will he just be stopping by for a quick fan-service cameo, or will he be intimately involved in the plot and giving Nick Fury (Samuel L. Jackson) a hand?
The former seems far more likely, as it'd be fully in-tune with Coulson's presence in earlier MCU films. He'll probably have a few brief scenes scattered throughout the movie and get some easy laughs, but stay in the periphery for the big-picture stuff.
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