A case is presented of a 35-year-old black African male anesthesiology resident, found dead in his apartment. At the scene a syringe, butterfly intravenous line and a bottle of Versed (Midazolam) were recovered. A comprehensive screen for common drugs of abuse and therapeutic agents failed to detect any drugs in blood and urine. The blood ethanol concentration was 0.06 g/dl. A GC/MS SIM assay for midazolam was developed. A sub-therapeutic midazolam blood concentration of 7.5 ng/ml was detected and concentrations (ng/ml or ng/g) in bile, urine, and liver were 3.3, 7.5, and 96, respectively. The syringe fluid was then analyzed and found to contain only fentanyl, midazolam was absent. The blood fentanyl concentration was 4.9 ng/ml which is consistent with those reported in fentanyl fatalities. Fentanyl concentrations (ng/ml or ng/g) in bile, urine, and liver were 8.8, 5.0, and 5.9, respectively. The cause of death was ruled to be fentanyl intoxication and the manner of death undetermined.