This Is Us could easily be co-sponsored by Kleenex for all the eye-wringing it does on a consistent basis, but there was one particular episode in the drama's breakout first season that left everyone weeping like newborn babies.

"Memphis" wrecked us all with its story of William (Ron Cephas Jones) returning to his hometown of Memphis while flashbacks to his relationship with his mother played out. The real stinger came at the end, when William passed away with his son Randall (Sterling K. Brown) at his side.

"That was really hard to shoot because I felt like I was losing Ron" Susan Kelechi Watson, who plays Beth, told TVGuide.com at a recent This Is Us event in Los Angeles. "Every time I looked in his eyes there was that sadness of like, 'this is my last day, you know, on set, or my last episode.'"

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"We knew [William's death] was coming, but we didn't want to do it," Brown said. "But once we did it and got it over with, the rest of the episode was such a joyous feel-good occasion of a father and son getting to know one another, that we got a chance to get over the tears so we could just enjoy each other's company."

As for Jones, he looks back on it fondly, and says all the difficulties and emotional weight combined to make something special. "It was a mystical, magical day for me."

This Is Us returns this fall on NBC.