The underlying question of any good Captain America story should be "What's the point of Captain America?" Essentially, what use do we have for a star-spangled propaganda icon from the '40s whose biggest skill is punching bad guys in the jaw? Captain America: The Winter Soldier does well to answer that question, using the hallmarks of the '70s government-paranoia thriller to pit our very old-fashioned hero against a very current anxiety: the government's deepening surveillance of every aspect of its citizens' lives.

Much like last fall's Thor: The Dark World, The Winter Soldier manages to slot into Marvel's superhero-movie formula without just coming off as a cog in a larger machine. Someone with very little knowledge of the "Marvel Cinematic Universe" could sit down and enjoy what is a largely rollicking action thriller without feeling too lost. Cap's backstory (he's a World War II super-soldier who recently got unfrozen in the modern era!) is laid out quickly and painlessly. The two major plot twists are nicely telegraphed without feeling obvious. The whole thing is maybe ten minutes too long, but it moves along at a nice clip, varying the frequent action beats  to keep things from feeling one-dimensional. There's a stealthy takedown of a hostage situation! There's a car chase! There's some appropriately large-scale business with a bunch of helicarriers to cap things off!

Directors Anthony Russo and Joe Russo, a surprise pick given their background in TV comedy and spotty film history (Welcome to Collinwood and You, Me and Dupree hardly scream $170 million action epic), are just the latest and best examples of Marvel understanding that telling a story cleanly and effectively is more important than having a proven track record with big budgets. The Russo brothers' pitch is simple: placing Captain America in the framework of a nervy conspiracy film, like The Parallax View or Seconds, except he flings his metal shield around a lot more.

We begin with Cap (Chris Evans, of the broad shoulders and square-set jaw) running missions for catch-all worldwide intelligence agency S.H.I.E.L.D., introduced as a throwaway joke in Iron Man and expanded on with every subsequent Marvel film as an increasingly powerful and increasingly suspect shadow-CIA. We know its head Nick Fury (Samuel L. Jackson), and here we're introduced to the shifty Alexander Pierce (Robert Redford), an inspired and lucky piece of casting. Redford feels institutional just standing there, representing 40 years of cinema history, inviting you to trust him even though you know something's wrong. Cap's creeping realization that something is rotten in the state of Denmark is better-earned as a result.

The Russo Brothers and screenwriters Christopher Markus and Stephen McFeely's other main inspiration is Ed Brubaker's hallmark run in the Captain America comics, which introduced the silent, machine-like "Winter Soldier" assassin character. He's the main villain of the film, and his origin (easily guessed by anyone with an IMDB account) is essentially unchanged, though hardly as shocking to a cinema audience as it was to comic book readers. The Marvel movies' biggest challenge has always been balancing the appeal between hardcore fans and the casual moviegoer: like all of them, The Winter Soldier has its moments that will prompt gasps and cheers from a small pocket of the crowd, but not at much detriment to the larger experience.

The disadvantage of the Marvel formula is that The Winter Soldier has the same cookie-cutter visual approach favored in all these films. The Russo Brothers wisely have Cap deploy his shield, quite creatively, as much as possible in action scenes, a marked improvement on the first Captain America film (which told a lovely little story and then turned into a snore-fest when it was time for fighting). Still, the action is a little choppy at times, mostly because it's almost entirely hand-to-hand stuff. Cap's two main sidekicks are Black Widow (Scarlett Johansson) and Falcon (Anthony Mackie), and both enjoy punching and kicking more than anything else (Falcon does get to fly around a little bit, but he mostly spends that time dodging enemy fire).

The Winter Soldier is the first Marvel movie, outside of The Avengers, to healthily dip into the universe's growing ensemble cast without it feeling forced. Since Cap is unfailingly idealistic and puppy-eyed (anything else would feel inauthentic), Johansson is an ideal foil as the Widow, a seen-it-all agent of death. Cobie Smulders pops her head in as Fury's deputy Maria Hill and leaves you wanting her to stick around. Garry Shandling's Senator Stern, a one-joke character from Iron Man 2, is brought back to play an actual small role in proceedings. The attention to detail makes worse films seem better in retrospect and confirms for the super-fans that Marvel knows what it's doing. Continuity is critical to this whole operation.

By far the best thing about The Winter Soldier is that it knocks down a lot of the infrastructure the previous films had created, and it does so in a way that feels organic and refreshing for the Marvel world at large. Essentially, the twist makes sense both for a Captain America movie and for everyone else, and it leaves the right threads dangling to actually whet the appetite for future projects. The Winter Soldier is very much aware of its purpose in a larger scheme, and by embracing it, manages to stand on its own as one of the more-memorable action films of the last few years. That's an achievement that seems grander and grander in retrospect.