Four best friends in their late-60s decide to escape retirement and throw a Las Vegas bachelor party for the only one of them who has remained single.

Carl Fredrickson, a retired balloon salesman, is part rascal, part dreamer who is ready for his last chance at high-flying excitement. Tying thousands of balloons to his house, Carl sets off to the lost world of his childhood dreams. Unbeknownst to Carl, Russell, an overeager 8-year old Wildnerness Explorer who has never ventured beyond his backyard, is in the wrong place at the wrong time -- Carl's front porch! The world's most unlikely duo reach...