Canadian boffins say they have developed a fearsome paralysis ray technology which caused test animals zapped with it to "turn blue and become paralysed". The effect is claimed to be "reversible", but is often fatal.
Chemistry prof Neil Branda and his colleagues achieved their startling effects by drugging their test animals with a fearsome ultraviolet-sensitive concoction, which they refer to as a "Photocontrolled Molecular Switch" - effectively a deadly remotely-activated poison.
Having stuffed their victims with this terrifying compound, the boffins then "irradiated" them with a particular wavelength of ultraviolet rays. This tripped the UV-sensitive "switch" compound, causing instant flaccidity and empurplement.
Branda and his pals then tried out the reversibility part of the kit, zapping the creatures with a different ray intended to turn off the switch and return to them control of their own bodies.
This didn't work nearly as well. "Many [of the test subjects] lived through the paralyze-unparalyze cycle", report the boffins.
The research has been widely reported as mimicking the effects of Star Trek phasers set to "stun". However we feel that Starfleet would surely refuse to accept a non-lethal weapon which firstly required every target to be given a cocktail of ray-activated chemicals and then despite such elaborate preliminaries was nonetheless fatal in many cases.
No, this isn't any Star Trek phaser. Furthermore the fact that it turns its victims blue seems somehow to lend the kit a vaguely gothic air. We'd envisage it more in some sort of late-steampunk setting, in which an insane genius - quite possibly a foreigner of some type - might plot to exterminate the population of London by lacing the capital's beer and liquor supplies with beam-sensitive paralysis poison. Then, preparations complete, a titanic death-ray installation would play upon the helpless city from some suitable elevated position - aboard a zeppelin dreadnought, emplaced in a hidden Moon base etc.
However it's important to note that so far the technology is verified to work only on pinhead-sized nematode worms, so there's probably no need to dust off one's steampunk-hero weapons - elaborate revolver, cricket bat, umbrella-sword, little-known oriental grappling technique etc - just yet.
If on the other hand you are in fact a sinister foreign scientist hell-bent on rendering the British Empire headless at a stroke and enslaving the survivors, you should read Branda & Co's paper. It's called A Photocontrolled Molecular Switch Regulates Paralysis in a Living Organism, and it's published in the Journal of the American Chemical Society (JACS), here. ®