This article was first published in The Montreal Gazette.
The blades descend as they have done many times before, threatening to impale the magician’s assistant lying inside the box. But this time the outcome is different. The illusion has been tampered with so that one of the blades does not retract fully as designed and slightly pierces her skin.
Nothing seems out of the ordinary until minutes later when the assistant collapses and dies. An autopsy reveals that the victim had actually been poisoned. A deadly toxin extracted from the skin of a South American “poison dart frog” had been applied to the blade. And so unfolds the plot on an episode of the entertaining British television series Midsomer Murders. Can this really happen? Definitely!
There are over 175 species of poison dart frogs in the family Dendrobatidae; all have bright coloration (aposematic coloration), which warns predators of their toxic skin secretions. They are small frogs, most are no bigger than a paper clip. They have a long, sticky tongue that darts out and captures their prey.
Phyllobates terribilis is appropriately named. It is so poisonous that natives only have to scrape a dart across its back to make the dart deadly. John Daly, the scientist who at the National Institutes of Health isolated and characterized many of the frog poisons in the 1960s, declared that he wouldn’t touch that frog because it had enough poison on its skin to kill a person.
Daly was also able to trace the origin of the poison to ants, small beetles, millipedes and mites on which the frogs dine. All these contain alkaloids that the frogs’ enzymes convert into toxins, the most notorious of which is batrachotoxin, so potent that one-hundredth of a milligram, too little to be visible, can be lethal to a human. Batrachotoxin opens sodium channels on nerve cells and the massive influx of sodium then impairs the neuron’s ability to send signals to muscles. Respiratory paralysis results. The only creature that does not have to fear Phyllobates is the “fire-bellied snake,” a small, harmless snake that has developed an immunity to frog poison and actually feeds on the creatures.
Epipedobates tricolor is a poison frog found in Ecuador from which Daly and colleagues extracted yet a different toxin they named epibatidine. While extremely toxic, it was also found to have a painkilling effect, some 200 times as potent as morphine. This was determined by the standard test in which a rat is placed on an electrically heated plate causing it to leap into the air. If the rat is injected with a pain killer, it will remain on the plate for a longer time. In general, the rodent will ignore the heat at a dose of one milligram of morphine per kilogram body weight, but the same effect can be achieved with a dose of only five micrograms per kilogram of epibatidine, accounting for the 200 times greater potency. Furthermore, if a rat given morphine is injected with naloxone, a chemical that neutralizes the effect of opioids, it recovers its sensitivity to pain.
Surprisingly, this did not happen with epibatidine, suggesting that its painkilling effect was due to a different mechanism and therefore would not lead to addiction. Indeed, instead of stimulating opiate receptors, epibatidine binds to acetylcholine receptors and inhibits pain signals from being transmitted. While at first there was great hope for epibatidine as a potent non-addictive pain killer, it turns out that the difference between a therapeutic and toxic dose is too small for practical utility.
While the magical murder on stage in Midsomer Murders is fictional, there have been real injuries and deaths associated with magicians pursuing their craft. Japanese magician Princess Tenko was seriously injured while performing the “The Spike Illusion in the face of Death,” an effect similar to the one seen on the television show. She was supposed to escape from a cabinet before it was pierced by 10 metal swords, but something went wrong and she suffered injuries to several ribs and her cheekbone, barely avoiding being stuck in her eye by a sword.
Amateur Australian magician Vivian Hensley wasn’t so fortunate. In 1938, Hensley was performing his version of an illusion originated by Houdini in which he pretended to swallow a thread and some razor blades followed by dramatically drawing the blades from his mouth, neatly strung on the thread. Hensley’s version involved swallowing a whole razor and then reproducing it. This was done by pretending to drop the razor into his mouth but actually slipping it into his coat sleeve. After some vigorous chewing and swallowing, he would pass his hand before his mouth and produce the blade from his sleeve, apparently having regurgitated it. This time, though, the blade slipped out of his hand and down his throat, triggering an involuntary swallowing reflex. He was taken to a hospital by ambulance where surgery to remove the blade was performed, but the damage to the gut had been extensive and his life could not be saved.
Gilbert Genesta, an American magician and escape artist, also met doom in 1930 while attempting to reproduce another Houdini effect, the classic “milk can escape.” In those days, milk was delivered to stores in metal cans of a size that was just large enough to accommodate a person. A handcuffed Houdini would squeeze into the can, which was filled to the top with water and sealed with a padlocked lid. There was no question that the magician was totally immersed in water with no air to breath. A curtain was placed around the can and within a few minutes a breathless Houdini emerged with the can still being totally sealed.
Genesta had reproduced this act many times as an homage to Houdini, the secret being a gimmicked lid that could be opened from the inside without having to remove the locks. That fateful day, he was unaware that the milk can had been dropped in transport, resulting in a dent near the escape hatch that made opening the hatch impossible. By the time his assistants noticed that he was taking too long to escape, it was too late. Genesta had drowned.
While there are no known murders by frog poison in magic shows, or anywhere else, frogs have played a role in at least one magic performance. David Blaine actually swallows frogs and regurgitates them. It is not a trick. He has trained his muscles to prevent the frogs from dropping into his stomach, keeping them in the esophagus from where they can be regurgitated at his will. He does not use poison dart frogs. That would be too much even for Blaine, who has mystified audiences with such life-threatening challenges as being buried alive or being encased in a block of ice for 63 hours. Chilling.
