Overview
Phantom Boy is a 2015 animated fantasy film directed by Jean-Loup Felicioli and Alain Gagnol and written by Alain Gagnol. The film stars Édouard Baer, Jean-Pierre Marielle, Audrey Tautou, Jackie Berroyer, Gaspard Gagnol and Noa Bernaoui-Savreux. The film was released in France on October 14, 2015, by Diaphana Films.
Plot
11-year-old Leo, dealing with cancer, reads a bedtime story to his younger sister Lily, before sharing a special secret with her: the illness has given Leo the ability to separate his spirit from his physical body, allowing him to hover and fly through the air in an intangible, invisible, and impalpable form, with his body remaining mostly asleep. He refers to this state as a "Phantom", but if he spends too much time away from his body, he will begin to fade away before disappearing entirely.
Meanwhile, NYPD Lieutenant Alex Tanner is demoted by his boss, Captain Simon, and assigned grunt work after he manages to catch two burglars robbing a supermarket, but blows up part of the building in the process. Leo is taken to the hospital for more tests, as his illness worsens. He laments over the loss of his hair and follows his mother home as a phantom. She weeps over Leo's health but does not let Lily see her cry.
From Wikipedia (CC BY-SA 4.0).