When dysfunctional adult, Al Clancy, mistakenly agrees to mind his smart-ass 10-year-old nephew, Karl Clancy, for a week, his job and home are placed in jeopardy. In a bold bid to save Al's job, they steal his mam's camper-van, become best friends and embark on a criss-cross adventure putting up posters all over Ireland. When things go wrong and the lads get cranky, one of them realises that the other one of them needs to grow up.