Warning: The following contains SPOILERS for Legends of Tomorrow's season 6 premiere.

The season 6 premiere of Legends of Tomorrow revealed a connection between team warlock John Constantine and the Arrowverse version of legendary magician Aleister Crowley. The episode also gave a subtle nod to the classic Hellblazer series and John's dealings with Crowley in the world of comics.

Born in 1875 in Warwickshire, England, Aleister Crowley was easily the most famous and infamous magician of the 20th century. A flamboyant figure who loved flaunting his disrespect for authority and convention, Crowley was condemned in his native country for his libertine lifestyle, which included recreational drug use and casual sex with both men and women. Crowley went on to establish his own religion, Thelema, and declared himself a prophet, while joining several other esoteric orders as he traveled around the world. To this day there is some debate as to how much Crowley believed his own press or if his image as the self-proclaimed "wickedest man in the world" was all an elaborate hoax. Either way, it's easy to see why a conman-turned-wizard like John Constantine (who has lived a similarly seedy life) might admire the man.

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"Ground Control To Sara Lance" established that the Arrowverse version of John Constantine had a history with Aleister Crowley, despite the legendary wizard reportedly dying in 1947. Constantine claimed to have summoned Crowley from out of Hell and trapped him on Earth. He also claimed to have taken ownership of Crowley's infamous spellbook, The Book of The Law, which was reportedly dictated to him by an "alien being" known as Aiwass. It's worth noting that Crowley's use of the word alien was in the context of occult creatures in the same vein as H.P. Lovecraft's Cthulhu Mythos, which was the more common vision of alien beings until science-fiction began to eclipse fantasy in the speculative fiction of the 20th century. Unfortunately, Constantine's interview with the trapped Crowley led him to believe that Crowley was a kook rather than a powerful wizard and he had never really looked at The Book of The Law until Zari suggested they might use it to locate Sara Lance in outer space. To Constantine's surprise, the book truly was full of powerful magics he could barely manage.

Aleister Crowley in Hellblazer 96

Constantine's description of his encounter with Crowley offered a nod to Critical Mass, a storyline from the Hellblazer series which detailed Constantine's earliest comic book adventures. The circumstances were slightly different, with Aleister Crowley still being alive and confined to a campsite on the shore of Loch Ness in Scotland. While the exact circumstances were never detailed, John Constantine had apparently learned of Crowley's deception and trapped the old mage in a series of magic circles that kept him hidden from Hell's forces and other magicians, but which would set off the magical equivalent of a signal flare if he ever left the circles. This left Crowley living off whatever fish he could catch from the lake for the better part of seven years, waiting for Constantine to return.

The fact that Aleister Crowley and Critical Mass have both been referenced at the start of Legends of Tomorrow season 6 doesn't seem to be a coincidence. The series' fifth season finale ended with John Constantine winning back his soul from Hell and freeing Astra Logue, the young girl who John lost to Hell during a botched ritual years earlier. Critical Mass was the storyline in the comics where John Constantine managed a similar feat, freeing the souls of every child ever trapped in Hell, including Astra, in one of his rare victories. Of course, there was ultimately a price to pay for that noble deed, and it will be interesting to see if the Arrowverse Constantine suffers a similar setback in the year to come.

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