Tenchu 2: Birth of the Stealth Assassins is the recently-released prequel to Tenchu: Stealth Assassins (both Playstation games). This game has scantily clad women, big swords, and bad-ass ninja sneaking. A new Azuma Ninja, Tatsumaru, is introduced, and the story of how the Azuma Ninja were established unfolds.
The secind installment of the Azuma saga is bigger and better Tenchu 1. The game play doesn't change a whole lot, though the addition of water stealth does widen the terrain a bit. The biggest drawback of the game is play control; the occasional awkward camera angle can pop up when you need it the least, i.e., in close-quarter combat. Also, if you die in a mission, you have to start back at the beginning, no matter how far you were when you were cut down. All-in-all, though, this looks to be the next Playstation classic; it's definitely worth your money.