Britain’s most beloved “Nan” (Catherine Tate) goes on the road trip of a lifetime from London to Dublin as her grandson Jamie (Mathew Horne) attempts to reunite her with her sister, Nell (Katherine Parkinson). The trip doesn’t go quite as Jamie imagined because Nan has her own plans, getting them into all sorts of wacky situations along the way - partying with an Australian rugby team, dancing at an all-night rave - all with the police hot on their trail.