Taylor Swift is joining The Voice as a "mega mentor" for Season 17.

The "You Need to Calm Down" singer's role was announced by returning coaches John Legend and Blake Shelton in a funny promotional video uploaded to social media on Monday (September 16). In the short clip, the musicians discuss the mystery mentor's arrival and act like they have no clue who the person will be.

"I hear we have a Mega Mentor," the "All of Me" hitmaker says before Shelton replies, "Yeah, but I don't know who it is. I know it's supposed to be a big star."

"Yeah, I think the person is like one of the most successful people in music but…" Legend adds before the country singer jokes, "That's true, but I can't be 'cause I'm a coach."

Swift then casually walks out of the trailer behind them as her single “ME!” begins to play.

"We promise that you’ll never find another Mega Mentor like her," the show jokingly wrote in the promo video's caption on Instagram. "See you soon @taylorswift."

Swift will join Legend and Shelton, as well as coaches Kelly Clarkson and Gwen Stefani, to offer advice to all the contestants and help each team prepare for the singing competition's  Knockout Rounds, which begins in late October. Normani, Will.i.am, Usher, and Darius Rucker will also appear as mentors this year.

The 29-year-old pop star previously served as the "mega mentor" on Season 7 of The Voice, as well as performed "ME!" on the Season 16 finale with Brendon Urie earlier this year.

The Voice premieres September 23 on NBC.

Taylor Swift's Hottest Red Carpet Photos