WARNING: The following contains spoilers for Suicide Squad Annual #1, on sale now from DC Comics.
Between the comic books and live-action film, Rick Flag has not had an especially good year. Kicking off the Infinite Frontier era by being imprisoned in Belle Reve after threatening to expose Amanda Waller, Flag recently managed to escape from custody. Since then, the career military man has laid low while Waller's attentions have been focused elsewhere, plotting his next move against his former boss. As Flag resurfaces in a remote corner of the world, he recruits an old Arrowverse villain to help him plan his revenge: Sam Scudder, the original Mirror Master.
Flag was imprisoned in the deepest, darkest cell in Belle Reve until he was freed by the mysterious, masked antihero Red X after Waller had the Suicide Squad infiltrate Teen Titans Academy. While Waller and Task Force X set their sights on Earth-3 and the Crime Syndicate of America, Flag entered a hidden, subterranean bunker located underneath a desert. Vowing to create a squad of his own, Flag meets with Scudder who has been imprisoned in the bunker for some time. To Scudder's surprise, Flag isn't offering him a chance at clemency by serving on the Suicide Squad but rather to help him hunt Waller down and stop her multiversal plot once and for all. And as Flag approaches Scudder in Suicide Squad Annual #1 (by Robbie Thompson, Eduardo Pansica, Julio Ferreira, Dexter Soy, Chris Sotomayor and Wes Abbott), the military tactician reveals that he already has a man on the inside secretly keeping tabs on Waller.
Created by John Broome and Carmine Infantino in The Flash #105, Mirror Master has always been a prominent member of the Scarlet Speedster's rogues gallery. Scudder was killed during the 1985 crossover event Crisis on Infinite Earths before being resurrected at the start of the New 52 era and its subsequent DC Rebirth era. In the interim, Grant Morrison and Chas Truog introduced a new Mirror Master in the Scottish supervillain Evan McCulloch in 1989's Animal Man #8 while versions of Scudder and McCulloch would separately appear in the Arrowverse on The Flash to menace Barry Allen and Team Flash.
Mirror Master and Rick Flag team up while the Suicide Squad are in the middle of a crisis of Waller's making. Superboy stumbled across a separate bunker containing numerous clones of himself and discovered that one of the clones is currently serving on Task Force X. This exposure put Waller and the squad on the run from the DC Universe's superhero community although she is still intent on carrying out her multiversal ambitions. Waller now operates for the first time as a fugitive without the approval or support of the federal government.
Judging by Flag's resolve, his recruiting of Mirror Master onto his new team is just the beginning, with other sinister figures with an axe to grind with Waller sure to follow.
As Flag and Scudder plot their next move, the identity of Flag's mole on the inside is revealed: William Cobb, the murderous Talon from the Court of Owls. As one of the biggest wild cards in the hand that Waller has dealt for herself, a particularly epic and bloody showdown is sure to come.