The story is about a cube that has mystical powers being stolen by the Loki (Thor's half brother) to destroy earth and Nick Fury gathers all of the help he needs to stop Loki and get back the cube. Typical saving the world story but lets do a headcount on the Avengers:
Tony Stark aka Iron Man
The billionaire, genius, playboy, philanthropist with the awesome suit of armor and his hightech gadgets. He carries on his arrogant but funny attitude from Iron Man movies to this movie too.
Steve Rogers aka Captain America
Frozen in time, the good guy super-soldier is here in his future as part of the Avengers.
The god of thunder with his might Mjolnir hammer.
Bruce Banner aka Hulk
The calm and looking normal doctor. But as we all know, pretty much an indestructible and unstoppable green mean monster when angry.
Natasha Romanoff aka Black Widow
No superhuman abilities but a well trained super spy.
Clint Barton aka Hawkeye
No superhuman abilities either but a master of archery.
That makes up the Avengers with Nick Fury briefing them.
They are a team full of different personalities and wants. But in the end, they would need to work together as a team to fight Loki and his army.
Overall, it was a really good movie with each hero getting their time to shine. Both the action parts and comical parts are very well presented. The movie is almost 2 and a half hours long but it is definitely worth every second.
A must watch movie, especially if you are a fan of any of these superheros.