The season-long “Invasion” story arc comes to a close as Miss Martian (Danica McKellar) and Superboy (Nolan North) arrive too late to prevent Batman (Bruce Greenwood), Wonder Woman, Superman (North), Hawkwoman, Jon Stewart, and the Martian Manhunter being found guilty on Rimbor for the crimes The Light an The Reach framed them for. Back on Earth, Blue Beetle (Eric Lopez), Aqualad (Khary Payton), and Green Beetle (Phil Lamarr) fight off Black Beetle (Kevin Grevioux) and the remaining Reach troops who would rather see Earth destroyed than abandoned.
After taking down Black Beetle, at the cost of Green Beetle’s scarab, Blue Beetle discovers it may already be too late as Black Beetle has already put his plans in motion to destroy any evidence of the Reach’s genetic tampering on Earth by destroying the entire planet. In order to save the planet the remaining 40 Young Justice and Justice League heroes will have to work together with Lex Luthor (Mark Rolston) to find and destroy all 20 of the Reach doomsday weapons scattered across the globe.
Meanwhile on Rimbor, the finally freed Leaguers along with Icon (Tony Todd) and Hawkman must deal with the sudden arrival of War World under the command of Vandal Savage (Miguel Ferrer) who threatens a show of force in order to keep any new Reach-like threat from making Earth their next target. This storyline is oddly thrown away until the episode’s epilogue where War World mysteriously shows up on Apokolips and Vandal Savage makes a new friend.
Along with those already mentioned above, the final episode also includes appearances by Artemis (Stephanie Lemelin), Kid Flash (Jason Spisak), Nightwing (Jesse McCartney), Lagoon Boy (Yuri Lowenthal), Black Lightning (Payton), Static (Bryton James), Captain Atom (Michael T. Weiss), Captain Marvel, Green Arrow, Wonder Girl (Mae Whitman), Beast Boy (Logan Grove), Batgirl (Alyson Stoner), Hal Jordan, Zatanna (Lacey Chabert), Guardian (Kevin Michael Richardson), Bumblebee (Masasa Moyo), and the Atom (James Marsden).
The two man teams manage to take down all the devices except for a hidden one in the Arctic which Impulse (Jason Marsden) and the Flash (James Arnold Taylor) discover only after it has become active. Together the two speedsters and Kid Flash race and try to siphon off its power before the device goes critical. The three manage to save the planet but not without a cost as Wally West is caught up in the dissipating energy and, as the Scarab puts it, “ceases to exist.”
Aside from the loss of one of the team’s founding members the fallout also causes Nightwing to decide to take a break from the team, with Artemis’ blessing Impulse takes on the role of Kid Flash, Static becomes a full member, the Young Justice team takes their place alongside the Justice League in the Watchtower, and Lex Luthor becomes a national hero for developing the technology to stop the Reach’s doomsday devices (despite the fact he was part of The Light who brought them to Earth in the first place).
“Endgame” provides the opportunity to wrap up several storylines at once while laying the foundation for others should DC decide to bring the show back (in one form or another). It also gives screentime to as many characters as possible (even if many of the heroes don’t get a single line of dialogue). The death of Wally isn’t really necessary, but it allows Impulse to take his current New 52 role, provide Nightwing to gracefully bow out of action for awhile, and provides a lingering cost to a rough season for the entire team. And, as we know, speedsters lost in time have a way of making it home (even if takes awhile).