I finally got around to seeing Captain America 2: The Winter Soldier.
As I suspected, the movie assumes that you saw the Avengers movie. That's a tad unfortunate. I really could have used an exposition-heavy scene, where Nick Fury hands Captain America his business card. He explains who he is, what SHIELD is, and why he thinks Captain America is the perfect fit for their organization.
Since I didn't get any of that, I spent the first quarter of the movie wondering who everyone was, and what was going on. Eventually, I decided to stop asking questions, and to pretend that it's the same secret government organization that the Hardy Boys work for. The movie's plot could easily work as a 1980's Hardy Boys book, since they're mostly nonstop action/fighting.
The second half of the movie is way better than the first. The first half tries to be a mystery, which keeps you guessing who the culprits are. It definitely wasn't as good as it could have been, and there were parts where my reaction was not "Oh, how mysterious!" but rather "Quit wasting time and tell me what's going on, already." I think it takes over an hour before we get to the plot twist that the movie is named after, namely, the Winter Soldier is really [spoiler].
Once the movie switched from "figure out who the bad guys are" to "stop the bad guys", it became much better. There was a lot of action and explosions, and the plot twists were based on information we know, not information we don't know. If I had to rewatch the movie, I'd probably fast-forward through the first part. Bring on Captain America 3: Civil War next year!
*reads description of Captain America 3*
Oh, dang. Another movie which forces you to watch the Avengers first. I'm not playing that game!