After Tristram was saved, the hero who killed Diablo has been troubled, becoming increasingly reserved. One day he just disappears, muttering something about travelling east - always to the east. Turns out he took the soul of prime evil onto himself. Soon after this, evil follows in his wake, laying waste to Tristram and everyone in it. Evil has survived and it has a name; Diablo.

The roleplaying phenomenon that caught everyone's attention back in 1996 is back with five different classes, each with their own skills and playstyles. The game features four acts where the goal is once again to face and kill Diablo.