The Man Is Keeping Us Down

Your heroes have been working themselves to the bone. Victory is in sight! But what's this? Oppressive forces outside their control have undermined their plans.

Typically the work of a Strawman Political racist or sexist or some other kind of narrow-minded bigot. The heroes have failed through no fault of their own, but rather due to factors in the world beyond their control which are largely a problem with their society. Expect a Downer Ending with a possibly Anvilicious message about the real-world social ills that motivated the author to write this. Alternatively there's a message of redemption where the heroes manage to overcome the otherwise insurmountable obstacles. In this case it becomes an inspirational story. In either case, the villains tend to be treated more as a general group to be avoided/overcome/defeated/etc. than one man who has problems with the heroes.

Historical settings can frequently find justification without objections from the audience, but more modern settings tend to garner objections from the demographic being portrayed badly. When done well and properly thought out, a good case of fiction mirroring life can prompt change. Moral Guardians tend to be involved either way.

Compare with Glurge, where it's the villains or pitiable background characters who meet this fate -- the heroes are safe in siding with the morally upright side.

Film

 * The French film Z does this well, portraying the work of an unnamed junta taking power in an unnamed European country... but the Greek government that prompted the movie's creation is always mentioned in the same sentence when the film is described.
 * Most, if not all, of the works of Spike Lee fall under this trope.
 * Uwe Boll thinks this is why his films do poorly.
 * Parodied in Undercover Brother, in which there really is a "Man" who is keeping African Americans as second-class citizens and controls a massive secret organisation devoted to this purpose. Also parodied with "Conspiracy Brother", a parody of black activists who often goes on rants of this nature; however, he's also spectacularly ill-informed, liable to fly off the handle at the slightest provocation and construe anything as being part of a conspiracy to keep black people down regardless of how innocent or nakedly ludicrous it really is, and really rather stupid.
 * Crash (the non-Cronenberg one), according to some of the characters.

Literature

 * Nineteen Eighty-Four features a man in an oppressive dystopia finding a small measure of freedom, only to lose it when the secret police catch him.

Live Action TV

 * The Wire does this, albeit in a more nuanced manner than most - the failure of systems, and conflict between individual and group interests, are major themes of the story.