| Issue | #51 |
| Published | July 2007 [May 9, 2007] |
| Cover Price | 2.99 USD; 3.65 CAD |
| Pages | 38 |
| Editing | Mike Marts; Jeanine Schaefer (associate) |
| Notes | This is a tryptich cover and the extra pages are included in the page count. |
| Characters | Martian Manhunter; Mary Marvel; Captain Marvel; Justice Society [Dr. Mid-Nite [Pieter Cross]; Flash [Jay Garrick]; Green Lantern [Alan Scott]; Powergirl; Wildcat [Ted Grant]]; OMAC; Blue Beetle [Jaime Reyes]; Black Adam; Nightwing; Huntress; Big Barda; Mister Miracle; Catwoman; Karate Kid; Spectre [Crispus Allen]; Cyborg [Victor Stone]; Zatanna; Batgirl [Cassandra Cain]; Flash [Bart Allen]; Justice League [Batman; Black Canary [Dinah Lance]; Green Lantern [Hal Jordan]; Red Arrow [Roy Harper]; Red Tornado; Superman; Wonder Woman]; Green Arrow [Oliver Queen]; Robin [Tim Drake]; Red Hood [Jason Todd]; Supergirl [Kara Zor-El]; Steel [John Henry Irons]; Green Lantern [John Stewart]; Green Lantern [Guy Gardner]; Mr. Terrific [Michael Holt]; Ion [Kyle Rayner]; Monarch [Nathaniel Adam]; Firestorm [Jason Rusch]; Batwoman [Kate Kane]; Starfire; Hawkman; Adam Strange; Hawkgirl [Kendra Saunders]; Aquaman II [Arthur Curry]; Metamorpho [Rex Mason]; Atom [Ryan Choi]; Wonder Girl [Cassie Sandsmark]; Donna Troy |
| Genre | Superhero |
| Pencils | Andy Kubert (signed) |
| Inks | Tim Townsend (signed) |
| Colors | Dave Stewart ? |
| Notes | This is a tryptich cover and the extra pages are included in the page count. |
| Characters | Joker's Daughter [Duela Dent] (dies); Monitors; Red Hood [Jason Todd]; Mary Batson [Mary Marvel]; Bernice; VILLAINS: Darkseid; Desaad; Heat Wave [Mick Rory]; Trickster [James Jesse]; Pied Piper [Hartley Rathaway] |
| Synopsis | When a character dies, it sets off an unexpected ripple that will touch virtually every character in the DC Universe. [per solicitation] |
| Genre | Superhero |
| Script | Paul Dini |
| Pencils | Jesus Saiz |
| Inks | Jimmy Palmiotti |
| Colors | Tom Chu |
| Letters | Travis Lanham |
| Script | Dan Didio |
| Notes | Dan Didio talks about COUNTDOWN. DC hot list - COUNTDOWN #51, GREEN LANTERN CORPS #12 and NIGHTWING #132. House ad for COUNTDOWN #50. |