Batman: Arkham Asylum has you play as Batman. The Joker has taken control of Arkham Asylum, and you have to beat your way through its inmates, make your way past the island's security measures, and stop the Joker from unleashing an army of madmen on Gotham City.
It's a simple premise for a Batman game, and it's almost perfectly executed. Picture this: Four thugs are patrolling a room with machine guns. A direct attack is suicide, so you use a grappling hook to perch on a gargoyle. As one of the thugs passes underneath, you swing down, drag him up, and leave him dangling from the gargoyle shouting for help. You find another perch as two of the other thugs run to investigate. That leaves the final thug isolated, so you glide through the air and execute a perfect kick to his head that leaves him cold.
By the time the remaining two thugs get there, you're back in the shadows. They're discussing what to do next in panic-stricken voices. You can see their mood, and they're terrified. You pull out a Batarang and get ready to go to town...
And that's maybe a minute of gameplay.
The voice actors and character designs are excellent. Mark Hamill in particular remains the perfect voice for the Joker; you hear a lot from him, but it never gets old.
Puzzles are challenging, but not cripplingly so. The Asylum is massive, but you'll generally be able to figure out exactly where you need to go to continue the game's story.
Arkham as an environment is gothic, brooding, slightly mysterious, and almost definitely haunted. Speaking of which, special mention goes to the Scarecrow sequences. When Batman gets dosed with fear gas, he experiences progressive hallucinations, causing the asylum to gradually twist into a hellish environment where Scarecrow himself takes on a godlike, nightmarish aspect. These hallucinations also explain Batman's origin about as well as any comic book or film ever has.
If you have an XBox 360 or a Playstation 3, I can't recommend this game enough.