The slightly neurotic Peter (Robert Downey Jr.) is an expectant father, and his wife (Michelle Monaghan) is due to give birth in five days. He rushed to catch the plane, hoping to fly to his wife immediately to accompany her in childbirth. Unexpectedly, things went against his wishes, and he met Ethan (Zach Galifianakis), an actor who wanted to become famous, on the plane. Then, trouble followed. After a chaos, the two were kicked off the plane and included in the list of no-fly passengers. Even more unfortunately, Peter's wallet and documents were all taken away by the plane. In order to catch up with the birth of the baby in time, Peter had to choose to go on the road with the annoying Ethan. The two were forced to take a ride together and embarked on a road trip across states and provinces. When the neurotic man meets the weird man, what else is waiting for them on the road? In the end, can Peter catch up to welcome the birth of the child?