Erasmo is attracted to the idea, partly because he’s convinced that at some time in his life he committed a terrible crime that he cannot remember. Sounding like a character in a Kazuo Ishiguro novel, he describes “the anguish produced by the guilt and the fear of having killed somebody without remembering the act or the victim.” At one point he even wonders, wildly, if a childhood fight actually ended in another boy’s death, and his family kept the fact from him.

In another writer, these fears might simply be a subtle way to portray the compulsive, sourceless guilt of the political exile, and hypnosis a metaphor for the difficulties of memory. These devices work that way here, too, but they’re also plausible enough that when Don Chente vanishes, a startling urgency comes into the novel. What did Erasmo disclose in their sessions? If he flies home, will he be arrested, tortured and killed, as so many of his friends and relatives have been? Or is the doctor’s disappearance the consequence of a misunderstanding? “The Dream of My Return” is a pleasurable, light-footed book, yet its final scene, which takes place in the airport as Erasmo debates whether to board the plane, has the tension of a thriller.

His decision also represents the book’s most serious focus, politics and the individual. In interviews, Mr. Castellanos Moya has abjured the term “political novel,” and he treats the atrocities of El Salvador’s long, sad civil war only obliquely — they’re often the subject of conversation, but Erasmo obsesses primarily over his own problems, in flights of neurosis, fluidly translated by Katherine Silver, that are more reminiscent of the funny, self-loathing heroes of Philip Roth and Ralph Ellison than of any grimmer Latin American antecedent.

And yet “The Dream of My Return” is obviously political, in the sense that there are some people for whom life is unalterably political, whether they would like it to be or not. That’s Erasmo’s bind. Not one but two people close to him, an uncle and a friend, have the tic of repeating the same stories about their beloved dead over and over. Erasmo, who has elected not to be one of those beloved dead, still has to spend his life hearing and thinking about them — and, finally, deciding whether to give up the cursed prestige of exile to join them at home, and perhaps therefore under the ground.

The paradox of that choice is that his death would be meaningless, whereas his voice in the novel seems so meaningful. It’s not that “The Dream of My Return” is a perfect book — its population of secondary characters is uneven, and its women especially, including Erasmo’s wife, Eva, are sketchy figures — but that it has the intense aliveness of great fiction, the kind that gives human particularity to circumstances for which our sympathy might otherwise remain mostly notional. Erasmo can do more for El Salvador here than there, we feel. He shouldn’t go. Of course, that’s one of the dreams of modernist literature, whether realist or fantastic: that the more stories we tell each other about such tragedies, the fewer of them there will be. We’re still waiting for the results.