The Heffleys are off on a road trip! The chances of survival are... quite small to be honest. Greg's idea of a good summer is air conditioning and lounging in front of the television.
But his mum has different plans, and now his family are having an "authentic" summer, trapped together on a road trip. And Greg's soon battling petrol-station bathrooms, crazed seagulls, a fender bender and a runaway pig. But even the worst road trip can turn into an adventure - and this is going to be one that the Heffleys will never forget!