| Issue | #24 |
| Published | October 1963 |
| Cover Price | 0.12 USD |
| Pages | 36 |
| Editing | Julius Schwartz |
| Notes | Contains 2 stories. Letters page includes the information that Green Lantern 21 was written by John Broome, and illustrated by Gil Kane and Joe Giella. |
| Characters | Green Lantern [Hal Jordan] |
| Genre | Superhero |
| Pencils | Gil Kane |
| Inks | Murphy Anderson |
| Notes | Contains 2 stories. Letters page includes the information that Green Lantern 21 was written by John Broome, and illustrated by Gil Kane and Joe Giella. |
| Reprinted | in Green Lantern Archives (DC, 1993 series) #4 (June 2002); in Showcase Presents Green Lantern (DC, 2005 series) #2 (February 2007) |
| Characters | Green Lantern [Hal Jordan]; Pieface [Tom Kalmaku]; Carol Ferris; Bill Bowery; The Shark (first appearance; origin; villain) |
| Synopsis | A nuclear accident causes a common shark to evolve into The Shark, who battles Green Lantern until defeated and de-evolved back into a shark. |
| Genre | Superhero |
| Script | John Broome |
| Pencils | Gil Kane |
| Inks | Joe Giella |
| Notes | First appearance and origin of The Shark. Synopsis and character appearances provided by Donald Dale Milne. |
| Reprinted | in Best of DC, The (DC, 1979 series) #10; in Green Lantern Archives (DC, 1993 series) #4 (June 2002); in Showcase Presents Green Lantern (DC, 2005 series) #2 (February 2007) |
| Synopsis | Science information on: the sun's corona, venus fly-trap, radar, and gamma rays, accompanied by illustrations. |
| Genre | Fact |
| Script | Julius Schwartz |
| Notes | Information provided by Donald Dale Milne except writing credit provided by Bob Hughes. |
| Characters | Green Lantern [Hal Jordan]; Pieface [Tom Kalmaku]; Terga Kalmaku; Green Lantern (entire planet); Sinestro (imitation); Dr. Polaris (imitation); Sonar (imitation); The Shark (imitation) |
| Synopsis | A sentient planet summons Green Lantern and appears to attack him while attempting to "talk" to him. Green Lantern then removes an apparently sentient fireball and places it in orbit to cure the planet of both indigestion and loneliness. |
| Genre | Superhero |
| Script | John Broome |
| Pencils | Gil Kane |
| Inks | Frank Giacoia |
| Notes | The planet "Green Lantern" has NO Green Lantern powers, it takes the name in honor of Hal Jordan. The "imitation" characters are constructed by the planet. Character appearances, synopsis and notes provided by Donald Dale Milne. |
| Reprinted | in Green Lantern Archives (DC, 1993 series) #4 (June 2002); in Showcase Presents Green Lantern (DC, 2005 series) #2 (February 2007) |
| Letters | typeset |
| Notes | A letter from Phil Cetrone notes that the story "The Man Who Mastered Magnetism" in Green Lantern 21, was drawn by Gil Kane, and inked by Joe Giella: the editor does not refute this. A letter from Bob Beck notes that the same story was written by John Broome: the editor does not refute this either. Another letter from Jack Harris notes that he sent in the idea for the cover of that same issue, and the editor states that for providing the idea, he sent Mr. Harris the original art for the cover. Information provided by Donald Dale Milne. |