Four years after the second film, The Lost World, Alan Grant (Sam Neill) and Ellie Sattler (Laura Dern) have continued their paleontological careers but are working independently now; Ellie is married with two children, and Grant is still digging with his prot?g? Billy Brennan (Alessandro Nivola). He is approached by Paul (William H. Macy) and Amanda Kirby (T?a Leoni), saying they are wealthy thrill-seekers who want Grant to be their guide on an aerial tour of Isla Sorna. Grant is reluctant at first, but the Kirbys' promise of funding his dig gets the better of him.