Over the weekend, several Chicago residents were shocked to see a large blue light in the skies. This went up over a mile into the air and had a thin blue line that was met with a large blob of blue at its tip. Overall, it was quite an unusual sight and got people wondering about its purpose.

News of this light quickly spread on social media on platforms such as Nextdoor and elsewhere. Rather unpredictably, this also led to cliched Batman jokes. Unfortunately, it wasn’t the caped crusader. Instead, it was something a lot closer to home.

It turns out that this light spectacle was the result of a lavish Halloween party held at Soho House in the West Loop. The light was provided by a company named Nu-Salt who has worked with a number of NFL teams, musicians, and venues to put on a light show. Nu-Salt has nearly three decades of experience doing laser shows and this weekend they were used in the heart of Chicago.

Over the years, Soho House has been known to hold extravagant Halloween parties at their venue for the wealthier members of Chicago’s high society. Because of this, it makes sense that a huge laser company would be hired to provide an eye-catching spectacle. The light could be seen from far away, which shows just how powerful it was.