If there are some amateur detectives in your group, some luminol may help them crack the case. This is the actual stuff used by crime scene investigators to identify trace amounts of blood. Luminol reacts with iron in hemoglobin and produces a blue luminescent glow when blood is detected.  Ever wonder if something has gone down in that dingy motel room? If you’re stuck there, it’s probably best to leave the luminol in your bag.

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