David MacLean came to on a train platform in India with no idea who he was or how he got there. It was 2002; he was living overseas on a Fulbright grant, and the antimalarial medication he was taking, Lariam, had erased his memory.

Assumed to be a tourist on a bad drug trip, MacLean was taken to a hospital in Hyderabad to detox, and then moved to a mental institution while the Lariam left his system. The drug, one of the most common antimalarials prescribed to tourists, soldiers, and expats, has been known to cause hallucinations, vivid dreams, seizures, and severe depression. MacLean’s case of almost total memory loss is rare but not unprecedented.

In The Answer to the Riddle Is Me, MacLean—who’s taught writing at the University of Chicago, Columbia College, and the School of the Art Institute, and currently lives in Chicago—tells the story of the years after his memory loss, of picking up where he left off in a life he didn’t remember choosing. Once he was well enough to leave the hospital, MacLean returned with his parents, whom he did recognize, to his childhood home in Ohio, which he did not, and tried to piece together an identity. He had a girlfriend, a dog, a research project, and boxes of photographs; none of them seemed more than vaguely familiar. He had shelves of books with quotes written in the end pages, “rewritten by me, or a me, maybe even the me. The one everyone kept expecting me to be again. Or was everyone trying to keep me from being that person again?”

MacLean began to suspect he had been kind of an asshole: past e-mails revealed a few ugly breakups, the possibility that he had been about to cheat on his girlfriend, and a general emotional wariness toward MacLean on the part of his friends and family. This suspicion further complicated the solitary and uncharted path of life after amnesia. He describes himself in that period as a “newly stitched-together doll of myself,” maintaining relationships, jobs, and habits that meant virtually nothing to him, and questioning what, if anything, is ineffable in our lives.

MacLean’s book is a compelling look at what it’s really like to live with amnesia—a happenstance frequently portrayed and yet rarely understood—an investigation into the troubled history and use of Lariam, and a moving personal account of being given the rare but terrifying chance to start over.