Terry Gilliam’s 12 Monkeys (1995) was a commercial and critical success, but it is Gilliam’s least understood film, even on the basic plot level. Aside from recognizable debts to specific films such as La Jetée (1962) and Dr. Strangelove (1964), 12 Monkeys plays with a number of genres: apocalypse and postapocalypse movies, sci-fi, nuclear noir, and what is becoming known as “geek dystopia.” This volume in the Constellations series examines Gilliam’s film—and briefly the TV series based on it—in the context of post-apocalypse movies and with an eye to the film’s major themes, including mental illness, conspiracy theories, the impossibility of human closeness, and the nature of reality. It is the first to read 12 Monkeys’s portrayal of time travel in light of Einstein’s ideas about time and to ask what answers these ideas suggest to the film’s most basic philosophical predicament: the problem of free will versus determinism.