Spontaneous pneumothorax (SP) is an abnormal occurrence in which air enters the pleural space, increasing pressure that pushes on the lung, causing it to collapse in part or full. Diagnosis is made by physical exam and can be confirmed by chest X-ray (CXR), chest computed tomography (CT), ultrasonography, and other forms of imaging showing a collapsed lung. We present the case of a 35-year-old male cannabis user presenting with sharp sudden pains in the right chest, who presented almost 12 hours after symptom onset and was diagnosed with a 90% pneumothorax of the right lung. Symptoms, diagnosis, treatment, and risk factors are discussed.