Structural analogs of classic drugs, also called designer drugs, are a booming market due to the easy accessibility on the internet and their legal status. One of those ‘legal highs’ is an analog of phencyclidine, namely 3-methoxyphencyclidine (3-MeO-PCP). Very few fatalities have been reported where 3-MeO-PCP contributed to the death of an individual. We present the first fatal case in the Netherlands and one of the few worldwide. Postmortem biological samples and the presumed abused unknown substance, sold as ant poison, were obtained. 3-MeO-PCP was detected, and the resulting concentration was 152 μg/l in whole blood. The presumed taken unknown sample was identified as 3-MeO-PCP and thus linked to the victim. The cause of death was a combination of 3-MeO-PCP, amphetamine, and alcohol. Improved diagnostic skills are necessary to face these emerging novel psychoactive substances also in light of public health and social risks.