Ulises wakes up one day and finds that his girlfriend, Alma, is missing. He embarks on an intense search that reveals hidden aspects of her life which connect to the time they spent together to lead Ulises to investigate a professor of hers and her obsession with a book by Borges. When Bianca, Alma's twin, shows up, circumstances escalate quickly to make Ulises commit a crime just so he can find Alma again.