E. Nelson Bridwell and Jack Sparling introduce a brand new team, the Secret Six, in the April/May 1968 issue of their own book. Most series at this time had launched out of Showcase or Brave and the Bold, but Secret Six was an exception. The series had not been intended for its own book, though. House ads promoted it as being a new series for the comic Tales of the Unexpected. But that book would change its title to The Unexpected, and gain Johnny Peril as its cover feature instead.
As the story opens we see a stunt man, a fashion model, a stage magician, a nuclear scientist, a salon owner, and a drunken bum each answer the same summons, from a masked figure called Mockingbird. The six people gather, and meet each other for the first time. An airplane comes for them, flown seemingly by remote control. They board, don some basic uniforms, and are then addressed by their mysterious leader.
It turns out that Mockingbird has blackmailed each of the six people into working as his operatives. At this point, we learn the names of each of the members of the Secret Six, and what Mockingbird has on them. Tiger Force is a former boxer, who testified against the mob and is on the run, thanks to a new identity provided by Mockingbird. August Durant, the scientist, was the victim of a poisoning attempt, and is only kept alive by medication provided by Mockingbird. It really had not occurred to me until just now, but August Durant is the first black member of a team of heroes in the DC universe. It's kind of great that nothing huge is made out of that fact, as if there were nothing special about having a black guy on a team. Carlo Di Renzi, the magician, also got into trouble standing up to the Mafia, and is similarly medically indebted to Mockingbird, who is providing care for his injured son.
Lili De Neuve, the salon owner, was convicted of a murder she didn't commit, but Mockingbird provided a fictitious alibi which saved her life. King Savage, now a stunt man, was a p.o.w. during the Korean War who broke and talked, but Mockingbird covered that up and made him look like a hero. The last is Crimson Dawn, the model, who was an heiress who got taken by a scoundrel who stole all her money. Mockingbird provided a new life and identity for her.
We, and they, also find out that one of these six people really is Mockingbird, which means that none of them fully trust the other ones. Mockingbird gives them their first mission, which deals with Zoltan Lupus, who is trying to sell a new kind of nerve gas, which draws out all oxygen.
Through impersonation and infiltration the team ruin the villain's attempt to sell the gas, replacing it with laughing gas, which also saves Durant's life.
Later they put the real gas back, so Lupus winds up dying from his own trap.
It's a really solid concept, particularly at a time when superheroes were not in vogue. This feels an awful lot like the tv shows from the late 60s, Man From UNCLE and such, but the Mockingbird-blackmail element adds something special to it.