| 0 | - | cover | 1 | pencils: George Tuska; inks: George Tuska | D-13 [Richard Anthony] |
| 1 | Strange Mysteries Unsolved | comic story | 1 | script: Oppenheim Terrof; pencils: Oppenheim Terrof; inks: Oppenheim Terrof; letters: Oppenheim Terrof | |
| 2 | The Green Mask and the Taj Lamah Jewels! | comic story | 9 | script: Will Eisner; pencils: Walter Frame; inks: Walter Frame | The Green Mask [Michael Shelby]; Franz Weise (death); Thomas Henrich (refugee author); un-named daughter of Henrich; News Doakes; El Rikaf (villain, introduction); Boris (villain); Voss (villain); Lovensky (villain); Hans (villain) |
| 3 | - | comic story | 6 | script: Dick Briefer; pencils: Dick Briefer; inks: Dick Briefer | Rex Dexter; Cynde; Protoplasmen (villains, all die) |
| 4 | Mistaken Identity | comic story | 2 | script: Fred Schwab; pencils: Fred Schwab; inks: Fred Schwab; letters: Fred Schwab | Billy Bounce |
| 5 | Murder in a Monsoon | comic story | 6 | pencils: Cecelia Munson; inks: Cecelia Munson | Chen Chang |
| 6 | - | comic story | 3 | pencils: George Tuska; inks: George Tuska | Wing Turner; the Nazis (villains) |
| 7 | - | comic story | 5 | pencils: Klaus Nordling; inks: Klaus Nordling | Lt. Drake; Tony Brick (villain, introduction) |
| 8 | The Morgue Murder Mystery | comic story | 4 | script: Fred Schwab; pencils: Fred Schwab; inks: Fred Schwab; letters: Fred Schwab | Hemlock Shomes; Dr. Potsam |
| 9 | The Dreamer | text story | 2 | pencils: Bob Powell; inks: Bob Powell | |
| 10 | Captured by Sin Lee | comic story | 3 | pencils: Art Peddy; inks: Art Peddy | Captain Savage; Sin Lee (villain, introduction) |
| 11 | Fiends at the Fair | comic story | 6 | pencils: Charles Nicholas; inks: Charles Nicholas | The Blue Beetle [Dan Garrett]; Von Heuger (villain, introduction) |
| 12 | The Bridge Blasters | comic story | 4 | script: ? [as Noel Howard] | Inspector Bancroft (last appearance) |
| 13 | Fahid the Revolutionary | comic story | 6 | script: Bob Powell; pencils: Bob Powell; inks: Bob Powell | Agent D-13 [Richard Anthony]; Fahid (villain, introduction) |
| 14 | Countess Zita, Spy | comic story | 4 | pencils: John Lindermayer; inks: John Lindermayer | Denny Scott; Countess Zita (villain, introduction, dies) |
| 15 | The Murder of Glenwood Village | comic story | 4 | pencils: George Tuska; inks: George Tuska | Zanzibar; Marco Hawkins (villain, introduction) |