Four kids and a dog embark on the adventure of a lifetime -- the search for the end of the Rainbow. With the aid of computers and an irrepressible belief, they achieve the impossible, finding and riding the multicolored arc.

When mercenary "Hardball" Cutter discovers that the team he is working with is actually a group of IRA gunrunners, he decides to put a stop to their plans. Furious with Cutter, the gunrunners target him, his partner, and his family.