Jaw-dropping ending to 'This Is Us' season finale completely blindsides fans

WARNING: Spoilers ahead for the Season 5 finale of This Is Us.

During Tuesday's Season 5 finale of This Is Us, Kevin and Madison may not have ended up getting married, but, in the final moments of the episode — which flashed five years into the future — someone else, who literally no one was expecting, did.

The episode opened with Kevin practicing his wedding vows in front of the mirror. While viewers were led to believe it was for his wedding with Madison, we later found out that it was actually not at his wedding at all, but at his sister Kate's wedding. But isn't Kate already married? To Toby?

Early on in the episode, Toby revealed to Kate that he finally got a job offer. The kicker was that the job was based in San Francisco. Ultimately, Kate remembered that she made a wedding vow to Toby that she would care about what he needs more than what she needs for the rest of her life. Kate called her boss, Philip, to resign from her position. However, Philip would not accept her resignation, because she was simply too good at her job.

Later, Toby told Kate he would turn down the job offer but, ultimately, the two decided to double down on their love for each other and commit to a long distance relationship. Everything seemed fine on the Kate and Toby front, until the classic This Is Us plot twist ending.

Kevin is seen entering the bride's room prior to the ceremony to get clearance on a movie quote in his wedding speech, and it is Kate who steps out in a wedding dress. "This is the last time I'm doing this, so go crazy, brother," Kate tells Kevin.

Next door, the music teacher, aka Philip, aka the new Miguel is exiting his room as Kevin tells him, "Hey, listen, uh, you're OK if I do some British jokes at your expense, right?"

Fans' jaws dropped after finding out that, in the future, Kate and Toby aren't together anymore and, instead, Kate is getting remarried to the music teacher.

So, once again, This Is Us flipped the script on fans and left us totally hanging until the next season, which will, sadly, be the final one.

This Is Us airs Tuesdays at 9 p.m. on NBC.

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