There are many similarities and differences between Levithan’s novel and the 2018 eponymous film directed by Michael Sucsy. Both the film and the novel follow the story of “A,” who wakes up every day in a different body and has to live in it for 24 hours. One day he wakes up in the body of a teenage boy named Justin and falls in love with his girlfriend, Rhiannon.
One of the main differences between the film and the novel is, in fact, Rhiannon and A’s characterization. In the novel, A slowly learns how to navigate his life and tries to adapt to his current situation, while Rhiannon tries to understand him. In the film everything seems a bit rushed, as the director wanted the film to have an acceptable run time; thus, many of the important experiences that A goes through are excluded. Basically, the novel chronicles A’s life as he tries to discover his identity and figure out how his situation affects the people he cares about; the movie, on the other hand, focuses more on Rhiannon’s point of view and hardly touches upon the same social themes that the novel incorporates.