Neverwinter nights 2.
This game has it all. The story is quite complex, quite long, and always keeps you interested and guessing. Honestly, Neither mass effect 1 or 2, or dragon age 1 or 2 have a story that has as many layers and complex and well told as The story told in nwn 2 and its expansion motb. It is probably one of the best stories told ever in an RPG, because they took the time to flesh out every portion of the world, everyone has a reason for what they do, whether good, bad, inbetween. Everyone has a story behind them, and it all adds together into the plot of the game. EPIC is all that can truly be said for it.
The combat is straight up DnD, doesnt get much better than that.
The writing for the NPCs throughout the game whether friend, enemy, or part of your party, its all fantastically done. They truly fleshed out each character and gave them more depth than you have seen in any recent RPG.
Huge amounts of mods adding new worlds to explore, or new spells, skills, classes, huge multiplayer worlds to explore. This game has it all.
Dragon age, mass effect 1 and 2 are all decent choices also, but if you are truly looking for an rpg that has a superb story. you want NWN2.
Edited by Vhati - 4/2/11 at 10:00pm