略带神经质的彼得(小罗伯特·唐尼 Robert Downey Jr. 饰)是一个准爸爸,五天后就是妻子(米歇尔·莫娜汉 Michelle Monaghan 饰)的预产期。他冲忙赶上飞机,希望可以马上飞到妻子身边陪她生产。不料,事与愿违,偏偏 上了飞机遇上一心想成名的演员伊森(扎克·加利凡纳基斯 Zach Galifianakis 饰)。然后,麻烦也就接踪而至了。在一场混乱过后,两人被赶下飞机并列入禁飞乘客名单。更不幸的是,彼得皮夹、证件又通通被飞机载走。为了及时赶上宝宝的诞生,彼得不得不选择和讨厌的伊森共同上路。二人被迫一起搭上顺风车,展开了一次穿州过省的公路旅程。当神经男遇上怪咖男,路上还有什么在等着他们呢?最后,彼得是否赶得上迎接孩子的出生?In Atlanta on business, straight-laced and overly analytical architect Peter Highman is flying home to Los Angeles and his wife Sarah for the imminent birth of their first child. However, traveling by plane no longer becomes an option when he and a fellow passenger, aspiring actor Ethan Tremblay, are kicked off the plane, which was caused by Ethan's social inappropriateness, due to being generally unaware, exacerbated by Peter's temper at a situation against his sensibilities. Peter, who ends up without money or his suitcase, is forced to accept Ethan's offer of a shared car ride to Los Angeles, Ethan who is looking for his big acting break. For Peter, this partnership is one made in hell, but he feels he has no other choice. Peter obviously wants to take as direct and as quick a route as possible, while he is at Ethan's mercy as the person with the driver's license, car rental and money. They get into one misadventure after another on this trip, with the same issue at each misadventure being Ethan's ineptness as an adult combined with Peter's resulting temper. The questions become whether they will survive the trip together, and if so if Peter will make it home in time to witness the birth of his and Sarah's first child.