The film is set in Afghanistan, in a region both remote and poor. Here, underprivileged children live in acute poverty in a maze of abandoned sewer pipes that provide meagre shelter. A father sets out to find someone who can attend to his severely disabled son, a young boy who is unable to walk; Mirvais, one of the inhabitants of the pipes, is willingly hired to carry the boy around on his back. It is not long, however, before Mirvais's simple duties are extended by his new young master. Mobile for the first time in years, the boy sees an opportunity to use Mirvais for his own ends.