The first This Is Us Season 4 trailer that dropped Saturday (WATCH HERE) doubled as a major casting announcement, as the promo heralded the arrival of nearly a dozen new actors/actresses to the series. In addition to the previously announced Jennifer Morrison, the list of This Is Us rookies also now includes Morrison’s former House co-star Omar Epps, as well as Psych‘s Timothy Omundson, Revenge‘s Nick Wechsler and filmmaker M. Night Shyamalan. But who are they all playing? NBC isn’t saying, but the trailer offered enough clues for us to cobble together some theories.

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