Chicago's River North neighborhood is abuzz with Taylor Swift's latest promotional brain teaser. Swifties flocking to 25 W. Grand Ave. have been greeted by a huge QR code mural, raising speculation and excitement over the star's impending album "The Tortured Poet's Department." Fans gathered, phones in hand, in anticipation of the album set to drop this Friday, with devotee Whitney Hansen positing that the mural may harbor "Easter eggs for a music video that's coming out," as she stated to NBC Chicago.

Emblazoned with the mysterious letters "TTPD" and repeatedly featuring the number 13, the mural seems to be leaving enough crumbs for fans to piece together a puzzle, leading Swift enthusiast Dani Filip Bermudez to say, “If you do Taylor math, you add up the threes and ones, and you get 16, which is today's date. But I'm still waiting for more.” While an intrigued Kristen Blevins weighed in on the matter, sporting a Taylor Swift sweatshirt and speculating about the past 'red herring' messages relating to Swift's work: "It's a really good secret that she's kept," remarked Blevins to NBC Chicago.

True to form, the QR code's destination has played an elusive game with fans. Initially, Tuesday's scans produced an "Error 321" message on a YouTube short, but savvy followers of Swift are no strangers to such tantalizing tactics. By Thursday, the digital breadcrumb trail led to another short featuring a typewriter and the cryptic typing of a single letter: "T." The charade stretches back to February, with misdirects preceding the announcement of "The Tortured Poets Department" at the Grammy Awards earlier this year.

Meanwhile, CBS News Chicago reported fresh findings. Digital Producer Elyssa's trek to the enigmatic mural revealed not just the letter "T," but gave rise to collective Swiftie theories such as potential single titles or collaborative tracks with artists like Post Malone. Further intrigue has swarmed from reports of scattered murals worldwide—from Australia to Brazil—with other letters like "F" and "H" adding to the swirling speculation. And in Los Angeles, an art installation with a library card catalog bearing 72 slots invites even deeper fan involvement.

With the album release beckoning on Friday, both the physical mural at 25 W. Grand Ave. in Chicago and the tantalizing digital trail that Taylor Swift has laid out ensure a truly "enchanting" experience.