Marijuana is considered as the most popular illicit drug around the world. It has numerous cardiovascular effects with myocardial infarction (MI) being a lethal one. The negative physiological effects of marijuana are well-studied, including tachycardia, nausea, memory impairment, anxiety, panic, and arrhythmia. We present a case of cardiac arrest following marijuana use in a patient who had a normal electrocardiogram (EKG) on presentation but diffuse coronary vasospasm on left heart catheterization (LHC) with no obstructive lesion. The patient had a transient episode of ST elevation on EKG following the procedure which resolved with an increased dose of nitroglycerine drip. Synthetic cannabinoids are more potent and not detected on a regular urine drug screen (UDS). In patients with low risk for cardiovascular events, particularly young adults, presenting with symptoms of MI/cardiac arrest, marijuana-induced MI should be suspected due to the severe adverse effects of its synthetic component.