While driving under normal highway conditions, the sunroof detached from the vehicle while still in the closed position. This caused extreme danger to other drivers and property and could have caused a fatality if it would have hit a motorcyclist or other unprotected person. There was a recall for this (Recall Campaign 152: 2015-2016 Sonata Panoramic Sunroof) and the vehicle was delivered to the dealer during the recall period for inspection and presumed fix. There was no warning that anything was wrong previous to the incident.