What message is Taylor Swift sending with that mural on a Chicago building?

With the release of Taylor Swift’s eleventh album just three sleeps away, the pop superstar is drumming up hype the way she does it best — with a scavenger hunt.

On April 15, the Monday before “The Tortured Poets Department’s” debut on April 19, a curious mural cropped up on the side of a building in Chicago. The image is littered with “TTPD” letters and the number 13, telltale signs that this mural is meant for Swifties. At its center is a big QR code, and people have lined up to check it out.

Fans on TikTok who’ve investigated have found out that, when scanned with a smartphone camera, the QR code leads to a YouTube short on Taylor Swift’s official page: a brief clip with the message “Error 321.”

Swifties will remember that “Error 321” had cropped up in another message Swift had left her followers to decode earlier in the year.

A few hours before she announced “The Tortured Poets Department” at the Grammys in February, Swift’s official website had went dark and read the message:

Swifties were later able to decode some of the message. The jumbled “hneriergrd” phrase was an anagram for “red herring.” “DPT: 321,” if decoded backward, hinted at the new album’s title, “The Tortured Poets Department.”

It seems this QR code plotted in Chicago is the first of many clues Swift had plotted in her latest scavenger hunt. We’ll have to wait to see what else is up her sleeve.

This article was originally published on TODAY.com