Do combined double-length TV episodes count? In that case, one of my votes would be
Smallville: Absolute Justice. It originally aired on February 5th of 2010, and here's the basic rundown...
[Show spoiler]After being confronted by a so-called "friend" who calls himself Sylvester Pemberton, Lois' cousin Chloe is thrown into a nearby dumpster, while her acquaintance apparently fights someone with strange powers. Freeing herself moments later, Chloe finds the killer gone and Sylvester dead, his body impaled by large blades of ice.
Not long after, Clark helps Chloe investigate what she witnessed, which leads them both to a history reel of footage showing several accused "criminals" - Carter Hall, Kent Nelson, Jay Garrick, Alan Scott, Ted Grant, Abigail Hunkel, Wesley Dodds, and Al Pratt. By the time Clark discovers the team's headquarters, only Hall and Nelson remain, plus Pemberton's successor Courtney Whitmore. They reluctantly team up to catch the killer, revealed as the son of a comatose criminal previously called Icicle.
While all our heroes eventually win the day (Dr. Fate restores John Jones' Martian powers at the cost of his own life), it turns out that Icicle was a mere pawn, used as bait by the leader of the government agency Checkmate, which in turn refers to its members as belonging to "the suicide squad". This episode is also notable in DC Comics adaptation history, since Pam Grier starred as the first live-action Amanda Waller.