WARNING: The following article contains spoilers for Charlie's Angels, in theaters now.

Charlie's Angels has fun putting its own spin on a number of spy film conventions, ranging from weapons suppliers to leadership positions. Another of these twists on familiar genre features in the new film comes in the form of the McGuffin doomsday device: a weapon the heroes have to steal away to keep the world safe that drives most of the plot... without playing much of a role in the plot.

Charlie's Angels has the Calisto, a portable energy source that can be turned into a truly frightening weapon, and one which might be one of the best versions of the trope in recent memory.

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CALISTO

Calisto is a device designed by a number of scientists, including Elena (Naomi Scott) at the behest of their employer, the ultra-wealthy Alexander Brock (Sam Claflin). The device, when operational, is capable of being a handheld energy source. As a show of power, a handful of prototypes are more than enough to power an entire downtown tech building. Working with largely green energy, the device is poised to change the face of energy going forward.

But Elena is particularly worried about one aspect of the device. She and her team discover a flaw in the weapon that, if utilized by a skilled enough hacker, could cause an EMP surge. But it wouldn't just disable any machines caught in the way of the blast -- it can also severely damage the human brain of any person nearby when it explodes, resulting in internal shutdown and seizures. One of her co-engineers ended up in the hospital after one such experience, suffering from brain damage that left him without the ability to see color or speak. Elena initially tries to warn the company of this flaw and that she just needs time to isolate and fix it before it goes to market.

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DOOMSDAY DEVICE

The reason Elena initially goes to the Angels in the first place is that her boss Peter Flemming (Nat Faxon) refuses to throw off the production schedule that could see the devices spread around the entire world in short order. Even Brock himself is later revealed to have hired an assassin to kill Elena for trying to tell the Angels about the weakness, not understanding what she was really trying to stop. If the Calisto did become a norm all around the world, it could be weaponized all around the world. Suddenly, it becomes a lot easier to kill someone.

Elena specifically reveals that a skilled enough hacker could break into the device and set off the EMP. The device is damaged in the act, meaning the hack becomes untraceable. Just as an EMP bomb alone it's dangerous, but the fact that it's revealed to also have another sudden and terrifying way to kill someone, as shown in the film, is even more insidious: one of the guards of the building, Ralph (David Schütter) gets too close to one of the devices as it's setting off an EMP. Elena is unable to warn him in time, and he's caught in the blast. He collapses onto the ground, shaking. The Angels have to leave him behind, and security camera footage later confirms that he died from the incident.

At least initially, Calisto would be a major financial success if the Angels weren't able to stop it from being released. If someone was willing to bide their time and only use it once it had become ubiquitous, it could become a weapon capable of taking out nearly anyone on the planet at any given time. It's a frighteningly casual and easy way to kill someone, even just as a portable seizure bomb. It's lucky the Angels are able to reacquire them by the end, but it begs the question about what other accidental super-weapons they've come across over the years.

Written and directed by Elizabeth Banks, Charlie's Angels stars Kristen Stewart, Ella Balinska, Naomi Scott, Elizabeth Banks, Patrick Stewart, Djimon Hounsou, Jonathan Tucker, Nat Faxon, Noah Centineo, Sarah Bennani and Robert Maaser.

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