Tina Fey, Rachel McAdams, Lindsay Lohan, Tim Meadows and Amanda Seyfried are among the cast members sitting down for the reunion, and they're reminding folks there's one month left to vote ... and the clock's ticking.

Katie Couric joined the fun, moderating the reunion and filling in for Amy Poehler by dressing in character as Regina George's mom. Ya gotta see Katie nail a few of Mrs. George's famous lines.

Tina teased the reunion Friday in a special video encouraging folks to make sure they are registered to vote and to request a mail-in ballot. She also challenged fans to volunteer as poll workers.

Aside from voting, the 'Mean Girls' cast takes turns sharing their favorite memories from being on set, examining the teen comedy's pop culture impact and of course, dropping their character's famous movie quotes.