| Issue | #42 |
| Published | February 1966 |
| Cover Price | 0.12 USD |
| Pages | 36 |
| Editing | Julius Schwartz |
| Notes | Pencilling and inking credits per Julius Schwartz' editorial records. Inking formerly credited to Murphy Anderson and Bernard Sachs. Lettering credit from reprint in JLA Archives. |
| Characters | Justice League of America [Superman [Clark Kent]; Batman [Bruce Wayne]; The Flash [Barry Allen]; Green Lantern [Hal Jordan]]; Metamorpho [Rex Mason] |
| Genre | superhero |
| Pencils | Mike Sekowsky |
| Inks | Murphy Anderson |
| Letters | Ira Schnapp |
| Notes | Pencilling and inking credits per Julius Schwartz' editorial records. Inking formerly credited to Murphy Anderson and Bernard Sachs. Lettering credit from reprint in JLA Archives. |
| Reprinted | in Best of DC, The (DC, 1979 series) #31; in Justice League of America Archives, The (DC, 1992 series) #6; In Showcase Presents: Metamorpho (DC, 2005 series) #1 |
| Characters | Justice League of America [The Atom [Ray Palmer]; The Flash [Barry Allen]; Green Lantern [Hal Jordan]; Superman [Clark Kent]; Batman [Bruce Wayne]; Wonder Woman (Flashback; Cameo); Hawkman (Flashback; Cameo)]; Metamorpho [Rex Mason] (guest star); Unimaginable (villain) |
| Synopsis | When Metamorpho refuses membership, the Unimaginable demands to be admitted in his place. |
| Genre | superhero |
| Script | Gardner Fox |
| Pencils | Mike Sekowsky |
| Inks | Bernard Sachs |
| Letters | Joe Letterese |
| Notes | Lettering credit from reprint in JLA Archives. Credits for script, pencils and inks confirmed from Julius Schwartz's editorial records, provided by DC Comics (May 2007). |
| Reprinted | in Justice League of America Archives, The (DC, 1992 series) #6; In Showcase Presents: Metamorpho (DC, 2005 series) #1 |