This Is Us Says Goodbye to Rebecca in the Most Heartbreaking Episode of the Series

[Warning: The following contains spoilers for Tuesday's penultimate episode of This Is Us, "The Train". Read at your own risk!]

The day that This Is Us fans have been dreading has finally arrived. The NBC drama said farewell to its matriarch, Rebecca (Mandy Moore), in its penultimate episode, and the hour was the series' most heartbreaking yet. Yes, it tops even "Memphis" in Season 2 and "Super Bowl Sunday," because it strummed every emotional string this show has tuned over the past six seasons. 

The Pearsons gathered at the cabin as alluded for several seasons now to say goodbye to Rebecca in her final hours. The entire Pearson clan and their extended clan took their turns saying goodbye to Rebecca, who was unconscious in her hospital bed but heard all of their messages in a suspended dream state that resembled a moving train. As Rebecca moved through the train cars, greeting important people from her past and present as she went, she walked closer to death. 

The narrative device allowed This Is Us to bring back important people from the show's past, including William (Ron Cephas Jones) as Rebecca's guide through the train and Dr. K (Gerald McRaney) as the train's bartender, dispensing more wisdom as Rebecca made her final journey. Beth (Susan Kelechi Watson) got the tears rolling when she thanked Rebecca for raising Randall (Sterling K. Brown) and promised she'd take care of him from then on. Toby (Chris Sullivan) earned a laugh for asking if Rebecca loved him or Philip (Chris Geere) more. 

The real waterworks were saved, of course, for the Big 3, who were the last to say goodbye. Rebecca refused to move on to the final train car until Kate (Chrissy Metz) made it from London — she had been overseas taking her musical curriculum international — and the siblings got to say goodbye to their mother together. 

"This is quite sad, isn't it?" Rebecca asked William before going into the last car. "The end."

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"The way I see it, if something makes you sad when it ends, it must have been pretty wonderful when it was happening," William replied. "Truth be told, I've always thought it a bit lazy to think of the world as sad, because so much of it is. Everything ends. Everyone dies, but if you step back — if you step back and look at the whole picture, if you're brave enough to allow yourself the gift of a really wide perspective, if you do that, you'll see that the end is not sad, Rebecca. It's just the start of the next incredibly beautiful thing." 

If you weren't bawling by the time William finished that mini-speech, then you had to be when Rebecca finally laid down in the bed set in the center of the caboose only to find Jack (Milo Ventimiglia) waiting for her. 

There is still one episode left of This Is Us, and with Rebecca's death being covered it leaves the possibilities wide open for how the show is going to wrap up. Will we see how the rest of the family's life plays out? Will we revisit the key scenes of the Pearson family journey that we've followed for the past six seasons? Will we somehow require more tissues for that episode than we did for this one? 

There's still a week to ponder that, but in the meantime, we know that William was right. So far the journey has been pretty wonderful, and incredibly beautiful. 

The This Is Us series finale airs Tuesday, May 24 at 9/8c on NBC.