Set in the 1960s, this novel exploring the mysteries of the multiverse—and of human identity—is "a rare page turner that avoids the obvious traps." —The New York Times Book Review

Garrett Adams, an uptight behavioral psychology professor who refuses to embrace the 1960s, is in a slump. The dispirited rats in his latest experiment aren't yielding results, and his beloved Yankees are losing. As he sits at a New York City bar watching the Yanks strike out, he knows he needs a change. Then, at a bookstore, he meets a mysterious young woman, Daphne, who draws him into the turbulent and exciting world of Vietnam War protests and the music of Bob Dylan and the Beatles, and he starts to emerge from the numbness and grief over his father's death in World War II.

But when Daphne evolves into four separate versions of herself, Garrett's life becomes complicated as he devotes himself to answering the questions about character and destiny raised by her iterations—an obsession that threatens to upend his relationship with a beautiful art historian, destroy his teaching job, and dissolve a longtime friendship. The Daphnes seem to exist in separate realities that challenge the laws of physics and call into question everything Garrett thought he knew. Now he must decide what is vision, what is science, and what is delusion.

"[A] mind-bending experimental thriller." — CrimeReads

"An immensely interesting concept . . . dig[s] deep into psychology, philosophy, physics, and, most importantly, politics as Daphne shakes Garrett out of his indifference toward the cultural turmoil of the late '60s." — Kirkus Reviews

"Brett's imaginative, amusing debut will appeal to fans of Nell Zink." — Publishers Weekly

"This absorbing novel vividly mines the physics and psychology of reality, and the reader's reward is a moving story of love and loss." —Hilma Wolitzer, author of An Available Man