| Issue | #3 |
| Published | April-May 1973 |
| Cover Price | 0.20 USD |
| Pages | 36 |
| Editing | Jeff Rovin |
| Notes | Credits from GCD index of original printing. |
| Characters | Legion of Super-Heroes [Superboy; Triplicate Girl; Lightning Lad; Cosmic Boy; Saturn Girl]; Computo |
| Genre | Superhero |
| Pencils | Curt Swan |
| Inks | George Klein |
| Letters | Ira Schnapp |
| Notes | Credits from GCD index of original printing. |
| Reprinted | from Adventure Comics (DC, 1938 series) #340 |
| Characters | Legion of Super-Heroes [Ultra Boy; Matter-Eater Lad; Star Boy; Element Lad; Brainiac 5; Chameleon Boy; Phantom Girl; Lightning Lad; Saturn Girl; Superboy; Mon-El; Colossal Boy; Sun Boy; Light Lass; Cosmic Boy; Triplicate Girl; Shrinking Violet]; Computo; Proty II; Android Master |
| Synopsis | Brainiac 5's latest creation turns on its master and the rest of the Legion. |
| Genre | Superhero |
| Script | Jerry Siegel |
| Pencils | Curt Swan |
| Inks | George Klein |
| Letters | Milton Snapinn |
| Notes | Story continues in the next issue. One of Triplicate Girl's bodies dies in this story. No credits on item; credits from GCD indexes of other printings. |
| Reprinted | in Adventure Comics (DC, 1938 series) #340 |
| Script | Allan Asherman |
| Letters | typeset |
| Notes | Article on Legion adventures in different time periods. |
| Characters | Tommy Tomorrow; Brent Wood |
| Synopsis | Tommy is put on trial for the murder of Brent Wood. |
| Genre | Science Fiction |
| Script | Otto Binder |
| Pencils | Jim Mooney |
| Inks | Jim Mooney |
| Notes | No credits on item; credits from GCD index of original printing. |
| Reprinted | from Action Comics (DC, 1938 series) #240 |