Mystery Solved: Why Tina Fey and Lindsay Lohan Reunited

Ten years after Mean Girls hit the big screen, fans went wild on Tuesday when Lindsay Lohan Instagrammed a photo with her former co-star, Tina Fey (who also wrote the screenplay).

"Lovely running into an inspiring, funny, beautiful old friend!!!! #tinafey," Lohan, 28, captioned the close-up selfie. After 60,000 likes, and hundreds of "that’s so fetch!" comments, the picture disappeared. So what was behind their seemingly casual run in?

Well, Lindsay may have jumped the gun by sharing that pic. Entertainment Weekly revealed (perhaps earlier than they would have liked) that Fey, 44, and Lohan got back together for the magazine’s upcoming reunions issue. The picture was snapped during an exclusive photo shoot that will hit newsstands on October 17.

[Related: Tina Fey: Let's Get the Mean Girls Anniversary Party Started]

It’s still unknown what other cast members, if any, joined in on the fun. However, the 2004 cult comedy was packed with a lot of familiar faces aside from just Lohan (Cady Heron) and Fey’s (Ms. Norbury). Rachel McAdams shot to fame as the queen of mean, Regina George; Amanda Seyfried’s Karen Smith taught us that on Wednesday’s we wear pink; Amy Poehler was the ultimate “cool mom;” and Lacey Chabert’s Gretchen Wieners gave moviegoers one of the greatest one-liners ever with “You can’t sit with us!” Emmy-nominated Masters of Sex star Lizzy Caplan and Daniel Franzese, who played Janis Ian and Damian, respectively, rounded out the star-studded cast.

Caplan, Franzese, and Poehler all had a rendezvous of their own a week ago in West Hollywood. “Celebrating a bday and an Emmy nom last night for one of the greatest people you will ever meet #LizzyCaplan with our girl #AmyPoehler last night at the Chateau Marmont. #meangirls #northshore10yrreunion #damiansyearbook,” Franzese captioned the photo below.

News that a Mean Girls reunion was happening went into overdrive in March after Lindsay Lohan stopped by The Tonight Show. “When I was backstage I saw Tina, and she mentioned maybe doing some sort of reunion … She said she was talking to Lorne [Michaels] about it. She’s talking to the big boss,” Lohan told Jimmy Fallon.

Weeks later, Fey downplayed Lindsay’s remarks. “At most, it would be like a panel discussion with a plate of hot wings,” she quipped to Access Hollywood. “It’s definitely not a movie.”

Get your burn books ready and start counting the days until October 17 for the EW issue to hit shelves.