Taken from mobygames.com:

Following the defeat of the evil krill in Enchanter, the intrepid apprentice have become a full member of the Circle, under the command of the famed Necromancer Belboz. Very soon, however, the hero notices that something strange has been happening to the master. He frequently talks to himself and seems to be under some sort of a malevolent influence - until one day, he is mysteriously kidnapped. Looks like the brave Enchanter must venture on a perilous journey once again, and bring back the leader of the Circle.

Sorcerer is a sequel to Enchanter, and is part of the Zork universe. Like its predecessors, it is a text adventure, in which the player interacts with the game world by typing combinations of verbs and objects. The spell system from the previous game is back; a new feature is the protagonist's ability to drink magical potions, which must be done sometimes in order to solve the game's puzzles.

http://www.mobygames.com/game/dos/sorcerer