吉米·霍金斯（托马斯·霍恩 饰）的父亲是一名退休的美国宇航员，曾经在国际空间站工作过。吉米·霍金斯一直梦想着有一天能像父亲那样有机会到太空旅行，他的生活每时每刻都是天体物理学。 一天，吉米被选中参参与下一次航天飞机座位的选拔，他将与来之世界各地的同龄人们一起竞争，到底吉米能否梦想成真，成为一名宇航员呢……

Three young boys, Rocky, Colt and Tum Tum together with their neighbor girl, computer whiz Amanda are visiting Mega Mountain amusement park when it is invaded by an army of ninjas led by evil Medusa, who wants to take over the park and hold the owners for ransom. Kids and retired TV star Dave Dragon, who made his farewell appearance at the park at the time the ninjas appeared, have to break Medusa's vicious plans.