A headstrong solicitor's plan to offload her new born baby to her sister, is derailed when a vulnerable but opinionated teenager steals their taxi.

12-year-old Mully (Reid) has lost his mother and discovers his debt-ridden father stealing the charity money they've raised in her name. Grabbing the cash, Mully steals a taxi and is shocked to find a woman, Joy (Colman), in the back seat with a baby. She joins Mully on a wild journey across Ireland, stealing cars, hitch-hiking, catching ferries and breaking police barricades.