On February 3, 2024, a fatal drowning incident occurred in Cenote Nariz, Mexico, involving a local cavern instructor and two other divers. The three divers began their survey dive at 2:51 PM, and the deceased exhibited distress shortly after turning back towards the exit. Diver 2 attempted to assist but could not revive Diver 1, who moved away and ultimately drowned. Investigations indicated possible hypercapnia and mechanical issues with the rebreather equipment as contributing factors to the incident. The report emphasizes the need for better training and awareness regarding diving safety protocols to prevent similar tragedies.