WARNING: Extended playing of this game may cause your head to asplode from overexposure to craziness; you should play it
What happens when the world's craziest, most dangerous criminal takes over the world's craziest, most dangerous insane asylum? S**t happens, that's what. After apprehending Joker (what's this, like the thousandth time?) Batman wheels him to Arkham Asylum to be locked away; for some reason the guards thought it would be funny to underestimate him and act like Joker hasn't been in the asylum tons of times before. Anyway, Joker ends up running the whole island asylum and you have to find him and stop him; time to whip out the batarangs.
The game is a beat-em'-up with free flow style combat, that is you can easily jump from beating one guy to another guy and keep it going until everyone's beaten. This works pretty well as you will often find yourself fighting medium to large groups of thugs. To mix things up, there are segments where you get to go all ninja on people's ass, that is you have to stealthily take out armed thugs cause in this game, bullets REALLY hurt. Taking out enemies in this way let's you be creative cause as you get more gadgets, your options for taking out enemies silently increases.
This game is way better than the sum of its parts! That is the individual elements that usually aren't important in videogames make it more enjoyable. The Joker delivers terrific line after terrific line and I found myself anxiously waiting when he would speak (but that' just me). Batman's lines range from weak to good and everyone else gives off the mood you'd expect from them.
There is a certain fear factor in the game, both for the player and the enemy. You'll encounter parts where you must face your fears and areas where the game will try to startle you through various means. If you or someone you know startles easily, make them play the Killer Croc segment in the dark at night without Detective vision (it'll be funny).
While I still think the game is better than the sum of its parts, there are elements that keep it from true greatness. After finding character bios I found myself thinking "these guys are cool, why aren't they in the game?" and some boss fights are ridiculously easy, more so than the stealth segments (especially the final boss, which was a huge letdown). Also, I don't know where the Riddler was for the course of the game, but if I ever find out I'm going to plow his face through a wall, put explosive gel on it and blow him into next week.
Basically, unless you're an avid fan of the B-man, and plan on collecting every single extra in the game, you should probably rent or borrow this game, but it's definitely worth playing I think; wouldn't be surprised if the sequels on the way.