Once upon a time, Bob Munro (ROBIN WILLIAMS) was close with his young daughter. But Cassie (JOANNA "JOJO" LEVESQUE) is now a typical teenager who wants little to do with him or her mom Jamie (CHERYL HINES), thus reinforcing the need for their anticipated vacation in Hawaii with Cassie's 12-year-old brother Carl (JOSH HUTCHERSON).
Unfortunately for Bob, his boss at Vibe Soda -- Todd Mallory (WILL ARNETT) -- doesn't really care, especially since they're looking at the potential acquisition of another company. Accordingly, Bob must cancel their plans and instead head to Colorado for an important pitch meeting. Knowing that won't sit well with the wife or kids, he gets the idea to rent an RV and drive from Los Angeles to Boulder. They hate the idea, but he convinces Jamie it's for quality time with their kids and she reluctantly agrees.
From the get-go, most everything that can go wrong does, including the Munros meeting the Gornicke family at an RV camp. Travis (JEFF DANIELS) and Mary Jo (KRISTIN CHENOWETH) are full-time RVers, a happy go lucky couple raising and educating their kids - Earl (HUNTER PARRISH), Moon (CHLOE SONNENFELD) and Billy (ALEX FERRIS) -- on the road. From that point on, the Munros repeatedly try to elude them, all as Bob secretly tries to get his work done at night, covertly leads the trip toward his big meeting, and must contend with one setback after another.