Rocky himself was back at the Philadelphia Museum of Art on Monday morning, but it wasn’t just for a solitary training run.

As Sylvester Stallone said in a video posted to his social media accounts Monday, he was back in Philly “doing something extraordinary” and that fans will “be seeing it in a few months.”

What brought Stallone to town, the Greater Philadelphia Film Office told the Inquirer, was filming for a commercial, though the office could not say what the commercial was for specifically. The shoot, executive director Sharon Pinkenson said, was “just a one-day thing” and was wrapping up Monday afternoon.

Paparazzo HughE Dillon tweeted that he had happened upon filming, writing that many members of the cast for the commercial were “dressed as mini Rocky’s.”

Stallone initially teased an upcoming trip to Philly back in October, writing that he would “pay a visit to my tall friend,” meaning the famed Rocky statue at the Art Museum. The clip posted to Stallone’s Instagram showed the actor in front of the statue marveling at how the artwork, created by sculptor A. Thomas Schomberg in 1982, has been “touched by so many people."

The actor last made headlines with an appearance at the Rocky statue last April, when he was in town filming Creed II. At that appearance, Stallone rededicated the statue’s plaque alongside Mayor Jim Kenney, who presented the actor with a personalized Eagles jersey.

“It’s like I never left here,” Stallone said last year. “I am Philly, Philly is me. My life began here, you know?”