If you were hiking or running in Griffith Park earlier today and wondered who the hell chained a giant disco ball to a bench near the Observatory, well, it turns out the culprit is Katy Perry.

Perry is promoting her latest single, “Chained to the Rhythm,” with a series of disco balls strategically planted in cities all over the world. Fans can plug headphones into the balls and preview the new track, which sounds pretty much exactly how you'd expect a Katy Perry song emanating from a giant disco ball to sound.

The balls, which seem to have been installed overnight, also appeared in 21 other cities, including New York, Mexico City, London and Sydney. They're already a big hit with Perry fans.

LA Weekly