The Chicago Outdoor Film Festival is hoping to break the Guinness World Record for “the most people wearing Groucho Marx glasses” at tonight’s free screening of Duck Soup in Grant Park’s Butler Field. (The current record is 4,077, for an event organized by the Leukemia and Lymphoma society of Springfield, Missouri.)

The movie will start at 8:52 PM, but those interested in breaking the record (or nabbing the glasses) should arrive between 6 and 7 PM to sign in; participants will pose for a photo and video around 8:15 PM.