This is one of the most original games to come out in years. It is hard to say what genre it fits in, but I would go with side scroller /action. The game get right into the action, it begins with you and your girlfriend watching a movie and then, the movie comes to life and the evil monster kidnaps your girlfriend. You then get to go in and take the place of the now dead super hero. There is a really brief tutorial at the start and then as you gain new powers, there is a slight pause to let you know how they work.
The game itself is great. Original, action packed and loads of fun. The graphics are also very impressive. They are made to look like an old school cartoon and all the characters are short and stumpy looking. As you progress through the game you gain new abilities, such as zoom in and slow motion, not your typical super powers. However, since many of the enemies are in hyper speed and can easily kill you, these powers are very helpful. You do not have an unlimited supply, you have an ever charging special effects meter that, when it runs out, you turn back into yourself and can't do anything (you can punch and kick, but you're a wimp).
The game is very difficult, but what bothered me the most and caused me to put it down so fast, is that there is very few save points. If you have read any of my other reviews, you will know that I hate not being able to save when I want, or at least have spread out save points. But in Viewtiful Joe, if you loose all you lives (three usually) you have to start the whole level over, which is a good thirty minutes or more.
The game is said to be very hard and it is, but a lot of the difficulty comes from having to do the levels in one shot. However, if this is not a concern for you, then I would highly recommend this game. I assure you, it is one of a kind.
The effect of the zoom in and slow down (or hyper speed) are very well done and the enemies chage regularly, keeping the game original. It is also not a game that you can finish in one weekend, so you will get your monies worth.
Part two is scheduled for this year and from what I hear it will offer an easier mode no the non hardcore gamers.