Legit thought there was a medical emergency 

What happens here

This video captures a bystander's unexpected encounter with a live film production for the television series 'Chicago PD' on a city street. The scene depicts a chaotic sequence with actors portraying civilians running amidst debris and law enforcement personnel, featuring special effects like smoke or mist to simulate an incident. The observer realizes they have stumbled upon a movie set and expresses excitement about witnessing the production firsthand.