Mattia Pascal lives in a provincial town and has found himself, almost by chance, married, poor, and working as a librarian. He suffers from the stagnation of his existence and is terrified by the idea of living “thus, always, until death, without any change, ever…”.
Seeking a momentary escape, he flees to Monte Carlo, where he gambles at the casino and wins a substantial sum.
He then discovers that in his hometown the unrecognizable body of a suicide victim has been found, presumed to be him, Mattia.
This is the most felicitous part of the novel: briskly paced, ironic, rich in well-crafted portraits and an effective depiction of provincial life and the milieu of casino gamblers.
Upon the news of his presumed death, Mattia decides to disappear, to become another man, freed from all ties to the past,

with my conscience made virgin and transparent once more, and the vigilant spirit of my new self

.
This is, however, an illusion, for within deceit he cannot live authentically.
He becomes fully aware of this when he falls in love with a woman to whom he cannot declare himself.
In truth, Pirandello is not so much interested in the drama of Mattia Pascal the man as in the paradox of a character who has managed to deceive even death.
Is life not perhaps an immense mystery, Pirandello asks himself, and “all this mystery does not exist outside of us, but only within us,” and

what if death did not exist, but were merely the extinction of the wretched feeling we have of it

? In the second part of the novel, the author loses interest in the study of characters and situations, which become increasingly predictable and mundane, focusing instead on his cherished theme: life as an illusion, as a hall of mirrors reflecting consciousness—a consciousness that is, moreover, false and deceitful—of the self.
The narrative pace becomes slow and repetitive, the dialogues are in many instances redundant, and the book loses the freshness and originality of its opening pages.
The conclusion of the novel comes as no surprise.
Trapped within a web of lies, Mattia Pascal decides to stage a second suicide—that is, to die once again—and return to being Mattia Pascal.
Yet his wife has remarried, rightly believing herself a widow; thus Mattia Pascal, even having returned to “real” life, must continue to live in deceit and falsehood.
He is now, irrevocably, the Late Mattia Pascal.

The desire to “evaporate,” as the Japanese say, is one of the never truly voiced aspirations of every human being.
Can one retrace one's steps? Can one live another life? Pirandello seems to answer in the negative, not because he believes that what matters are the authentic relationships we maintain with people and with the environment in which we live, but because he is convinced that everything is an illusion and a deception.
This is the theme of Pirandello’s major plays, which, from a stylistic standpoint, hinge on the dialectic between characters—an extraordinarily effective device for unveiling the lie in which we live.
Transferred to the novel, this approach renders it ponderous, diminishing the pleasure of the reading experience.

Why read it? The momentum and irony of the novel’s first part compensate for the sluggishness of the second.

The Late Mattia Pascal