The Alchemist
Of course, the central irony of The Alchemist is the fact that none of the "patrons" of the magician know that it is Subtle behind the scheme. Adding to the irony is the fact that, before his role as the sought-after Alchemist, Subtle was an impoverished beggar on the street.
Doll Common
Doll Common is an integral part of the operation that she, Subtle, and Face run together out of Lovewit's house. The irony surrounding her character is that she is a prostitute who poses as a religious extremist who has read so much religious literature that she has gone mad.
Tranformation
While the transformations that the Alchemist promises are of course a hoax, the play does, ironically, showcase some important transformations: the transformation of Subtle into a respected magician, of Doll from a prostitute to a religious woman, and of Lovewit from a bachelor to a happily married man.
Status Quo
At the end of the play, the scammers are not necessarily punished the way one might expect. Instead, Jeremy/Face is able to improve his master's life and returns to his role as a butler. In this way, the play ends with the re-establishment of the status quo rather than the condemnation of the lower-class schemers, subtly hinting that their farce was an innocuous one.
