Showcase #22 was the issue of DC Comics "Showcase" series that had the first appearance of the Silver Age Green Lantern, and introduced several aspects of the Green Lantern mythology, including the characters Abin Sur and Carol Ferris. It was published in 1959, and written by John Broome and illustrated by Gil Kane and Joe Giella.
The first part of the story illustrates Green Lantern's origin, now familiar to comic book fans through decades of retelling and parody: alien member of the Green Lantern Corps (although that term isn't used here) Abin Sur has crash landed on earth and is dying, and sends out his psychic powers to summon test pilot Hal Jordan and bequeath him the Green Lantern paraphernalia. Having learned about his new powers, the next two chapters show Green Lantern fighting villains, and also setting up the romantic subplot where his boss, Carol Ferris, is also his romantic interest. Her father, the president of the Ferris Aircraft Company, goes on a two year sabbatical, leaving his daughter to run the company. And of course, in a parallel to the Lois Lane/Superman/Clark Kent love triangle, she falls for Green Lantern. In the more action oriented parts of our tale, Green Lantern fights saboteurs, in a series of battles that reinforce for him, and the readers, the nature of his powers, as well as its limitations (needs to be recharged ever 24 hours, weak to yellow).
I was familiar with the broad strokes of the mythology, but what was interesting for me while reading was how much this issue averted Silver Age Silliness. Interestingly, the villains that Green Lantern fought were not "super villains", but were depicted more as mobsters. No costumes or gimmicks, just violence. And despite the stringency of the Comics Code, the relationship with Carol is a little more adult and racy. (And even a little bit disturbing to modern eyes as Hal Jordan grabs his boss around the waist at work). Even Hal Jordan's face is drawn in a more mature, rough manner than the boyishly charming Superman. My take on the first story of Green Lantern is that is seems more like a spy or adventure story than a "Super-Hero" story. But the Silver Age being the Silver Age, by the second issue, the primary-colored monsters and leaps of logic would be running the show.
Also, since an original copy of this issue even in poor condition costs around $2,000 currently, I read it in a collection, meaning I didn't get to see the ads that would have been interspersed in the original story, which probably would have set the mood nicely.