The show features the cast as older versions of themselves, but as the actors who were on the show, not the characters themselves. They even hit a fan convention in the premiere episode.
But one key cast member was missing, and that was the iconic Luke Perry, who died earlier this year after suffering a massive stroke. Perry had played Dylan McKay for seven seasons during the original run.
In a key scene with the group, Tori Spelling admits that the group won't live forever, but "made something that will" in the show. They toast to the late actor and embrace, and there's also a moment of silence for their friend.
But the tribute wasn't over for the famed actor.
After Spelling decides to make a reboot of the show within the show (yeah, confusing), the episode ends with a flashback of Perry in the original series.
"Welcome to paradise, man. Welcome to your dream come true," Perry says in the old clip.
As if his loss in March didn't hurt enough, hearts broke all over again for the man who was the heart and soul of "90210."
Earlier this week, Doherty spoke to "GMA" about missing Perry on the reboot.
"It was surreal, all of us together again and sort of realizing that you're missing a key component, you're missing some heart," she said. "Luke was all heart and all humility and beauty and grace and humor and just grounding, earthy human being. So, he was missed sorely for sure."