Rachel McAdams makes a surprise appearance on "Saturday Night Live" on January 20.
CNN  — 

Regina George, meet… Regina George.

Rachel McAdams, who played the iconic character in 2004’s “Mean Girls,” appeared on the new episode of “Saturday Night Live” to introduce musical guest Reneé Rapp.

Rapp plays Regina George – the leader of cool-girl friend group “the plastics” – in the musical reboot of “Mean Girls” that debuted in theaters earlier this month.

“SNL” alum Tina Fey appears in and produced both versions of “Mean Girls,” which follows North Shore High School newcomer Cady Heron as she navigates public school and the dizzying world of high school cliques after having been homeschooled.

Adding to the “SNL” episode’s surprise cameo roster was an appearance by rapper Megan Thee Stallion, who performed “Not My Fault” with Rapp after McAdams’ introduction.

McAdams also appeared in a hilarious sketch later in the episode, which was hosted by “Euphoria” star and first-time “SNL” emcee Jacob Elordi.

In the sketch, McAdams played an aspiring actress who looks like the real-life “Notebook” actress, but says her name is actually Natalie Partman — not to be confused with Oscar-winning actress Natalie Portman. Elordi serves as the not-so-helpful working actor who gives pretty awful advice to an acting class.

The episode served was the first of 2024 after the long-running sketch show’s holiday hiatus.

The next episode of “SNL” will be hosted by “Madame Web” star Dakota Johnson and Justin Timberlake will be the musical guest.