The Green Lantern is often considered one of the most powerful heroes in the DC Universe, but during his very first team-up with The Flash, the Emerald Warrior had no choice but to give up his ring to the Scarlet Speedster.

Both the Hal Jordan version of Green Lantern and the Barry Allen version of the Flash have been long-time comic book best-friends, but their partnership originated a few years into the Silver-Age of Comics. During the late 1950's, DC decided to revive some of their older superhero properties, and revamp them for a contemporary audience. The first of these characters was Barry Allen, the second Flash following the original Flash, Jay Garrick. The Barry Allen version of the Flash developed his powers in a laboratory accident, being struck by lightning, and was inspired to become a superhero like the original Flash. The second of these new characters was Hal Jordan, the second Green Lantern following the first Green Lantern, arguably the most important DC Superhero, Alan Scott. Unlike the original Green Lantern whose powers came from magic, Hal Jordan's ring was a product of science fiction, given to him by the alien Abin Sur and powered by a battery in the form of a lantern. After being chosen by Abin Sur and the ring, Hal became one of many  to serve in the Green Lantern Corps.

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Barry and Hal would not meet until 1960's Brave and the Bold #28, the first appearance of the Justice League of America. However, the two heroes would not have a proper team-up until Green Lantern #13 in 1962, where Green Lantern was brainwashed into capturing the Flash for the alien race the Spectarns. The Spectarns wished to use the Flash's super-speed to break the barrier between their world and Earth, so the aliens could conquer the human race. Green Lantern eventually came to his senses and, after freeing the Flash and teaming-up with him, defeated the Spectarns. During this adventure, both Barry Allen and Hal Jordan learn the others secret identity, and they quickly became friends. An editors note at the end of the story revealed that this issue was the first in a series of stories for the two characters teaming-up. The second of these stories happened in The Flash #131, also released in 1962, where both heroes again fought alongside one another to defend the world from another alien threat.  Though their early adventures together are considered classic Silver-Age stories, one of their most interesting team-ups was their third adventure together.

DC Comics Gorilla City Flash Green Lantern

The third team-up between the two heroes was in 1963's Green Lantern #20, titled Parasite Planet Peril. When a phenomenon dubbed the vanishing plague causes people on earth to vanish over time, the Green Lantern and Flash team-up to try and prevent more people from vanishing. When the Green Lantern gets afflicted by the disease, he hands over his power ring to The Flash, hoping that the power of the ring could prevent himself from vanishing. This attempt fails and Green Lantern vanishes, leaving Flash, equipped with the Lanterns power ring, to combat this plague alone. Green Lantern did not vanish completely however, as he and every other person afflicted by the plague was actually shrunken down to the sub-atomic city known as Mikridion, run by creatures dubbed the Mikrids.

The Mikrids, living in a scientifically advanced culture, sought to capture humans in an effort to harvest their brain power to further enslave another captured species, the Bowerds. The Flash, remembering an off-panel conversation where Green Lantern believed the problem to be microscopic, builds a high powered microscope. Using the microscope, enhanced with extra power from the Lantern ring, Flash is able to confirm that a sub-atomic species exists, and speculates that it is responsible for the plague. The Flash manages to shrink down to Mikridion with the power of the ring, and with the help of the Green Lantern they defeat the Mikrids and free the humans and Bowerds.

The Flash is no stranger to wearing Lantern rings, with Barry Allen wearing a Blue Lantern ring during Blackest Night, but the fact that he was able to use the ring to such a degree raises a lot of questions. Hal Jordan had been on many adventures prior to this one, and had plenty of opportunities to learn about his ring along the way, but this was Barry Allen's first time using the ring, and he adapts to it with no problems. Barry was not only able to amplify his microscope using the ring, but shrink himself down to a sub-atomic level as well, one of the many odd powers a Green Lantern ring was capable of.

The Flash and Green Lantern Drawn by Alex Ross from DC Comics

Though Barry recalls that Hal told him with "sufficient strength of will" the ring is capable of doing anything, he still doesn't have the same level of experience that Hal does and shouldn't be capable of the feats he performs. One could make the argument that, since Barry saw Hal using the ring on prior adventures he would have an idea on how to use it, but watching someone perform a task doesn't automatically make you capable of doing the same thing.

However, this was not the first time, nor the last time, that an unexpected character wore a Green Lantern ring during the character's history. It makes far more sense for a fellow super-hero to be able to handle a Power Ring then, say, Jimmy Olsen for example, as characters like Olsen would be considered an ordinary civilian. The Flash is anything but ordinary with his heroic background and willingness to leap into action, it would make sense that he would have enough will-power to handle the ring. Given the context of the situation, with the Green Lantern slowly vanishing, it would make sense for Hal to give the ring to his friend, someone he would have little doubt could utilize its full potential. Many of the contemporary elements in the Green Lantern lore, such as the emotional spectrum, did not exist in the 1960's, and the power ring was simply a tool that anyone could use. Still, based their first proper team-up, The Flash could seemingly run circles around the Green Lantern when it comes to using the power ring, in either brightest day or blackest night.

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