Criminal Minds' Reid Dazzles Us With Details About a U.S. Army Flub — Watch

Do you know your Asclepius from your Caduceus? If not, Criminal Minds‘ Reid is here to school you — and in doing so, leave a local lawman’s jaw on the floor.

In the 13th episode of the CBS drama’s 13th season, titled “Cure” and airing Wednesday 10/9c, the BAU is called to investigate a series of D.C. homicides where cryptic messages are found inside the mouths of each victim.

In the exclusive sneak peek above, Reid and JJ (played by Matthew Gray Gubler and A.J. Cook) arrive at a murder scene to discover that the vic’s blood was used to scrawl some sort of symbol on the wall. But wait, isn’t that “snake coiled around a staff” the well-known symbol for “medicine”? Yes and no, Reid entertainingly and exhaustively explains — once you press PLAY.

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