OMITB Season 3: Only Hard-Core Mean Girls Fans Will Notice This Finale Link

"Mean Girls" fans get a little Easter egg in the third season of "Only Murders in the Building," as a treat.

Trust us when we say this is an extremely subtle reference, but even if it's a coincidence, it's a pretty great one. The third season of "Only Murders in the Building" premiered its first two episodes on Hulu overnight on Tuesday, August 8, and the tenth episode, which will serve as the Season 3 finale, is set to air on October 3, 2023. That noise you heard is the ears of "Mean Girls" fans perking up everywhere.

Thanks to a memorable joke in Tina Fey's movie, the date of October 3 is incredibly important to longtime "Mean Girls" fans, and it's even been marked as the movie's unofficial holiday. So why would "Only Murders in the Building" pick this auspicious day to close out their third season, and what other connections do the Hulu mystery series and the classic teen comedy share? Here's why "Mean Girls" and "Only Murders in the Building" have a lot more to do with one another than you fully realized.

What connections do Mean Girls and Only Murders in the Building share?

Beyond the Season 3 finale of "Only Murders in the Building" airing on October 3, there are actually plenty of connections between the Hulu original series and "Mean Girls." Chief among them is the presence of Tina Fey, who has played popular podcaster Cinda Canning in the series since Season 1. (Fey wrote and appeared in "Mean Girls," obviously.) When the show kicks off, Charles-Haden Savage (Steve Martin), Oliver Putnam (Martin Short), and Mabel Mora (Selena Gomez) all bond over how much they love the true-crime podcast "All Is Not OK in Oklahoma," an obvious parody of the genre-defining real-life podcast "Serial." That podcast happens to be hosted by Canning, and she returns to the show in Season 2 when it turns out that her assistant Poppy (Adina Verson) is behind the most recent string of murders.

Season 3 also sees the addition of "Emily in Paris" star Ashley Park as Kimber, a TikTok star perhaps hoping to go viral — even if that means resorting to murder. What does Park have to do with the "Mean Girls" franchise? She worked alongside Fey on the "Mean Girls" musical, starring in the original Broadway cast as Gretchen Wieners when the show came to New York in 2018. Just in case the October 3 and Fey of it all wasn't enough for you, Park is also a major "Mean Girls" connection, and it definitely feels likely that she's a part of this series thanks to knowing Fey, at the very least.

Why is October 3 known as Mean Girls Day?

So why exactly is October 3 even a big deal for "Mean Girls" fans? During the movie, new Illinois transplant Cady Heron (Lindsay Lohan) finds herself suddenly adopted by the high school's queen-bee clique, "the Plastics" — made up of Regina George (Rachel McAdams), Gretchen Wieners (Lacey Chabert), and Karen Smith (Amanda Seyfried) — only to discover that they're just as cruel as everyone says. With the help of her secret friends Janis Ian (Lizzy Caplan) and Damian (Daniel Franzese), she tries to take the ultimate queen, Regina, down... only to become just as awful as Regina herself.

This all comes back to October 3 when Cady decides that she needs to steal Regina's boyfriend Aaron Samuels (Jonathan Bennett), partly to take away Regina's power and partly because Cady's really carrying a torch for the guy. In the process, in Lohan's voice-over narration, she tells the audience that on October 3, Aaron asked her what day it was. "It's October 3," she replies eagerly, clearly seeing this as a sign that he likes her. This is why October 3 is "Mean Girls" Day, and why it's a nice little annual joke for enduring fans of the classic film.

"Only Murders in the Building" Season 3 drops new episodes on Hulu every Tuesday, and will do so until... October 3.