Third instalment of the popular CGI-animated franchise. While Scrat the squirrel is still trying to get his paws on that ever-elusive nut, Manny (voiced by Ray Romano) and Ellie (Queen Latifah) anxiously await the birth of their mini-mammoth, and Diego the sabre-toothed tiger (Denis Leary) wonders if he's growing too laid-back living the life of a pampered house cat. Meanwhile, Sid the sloth (John Leguizamo) gets into trouble when he creates his own makeshift family by hijacking some unusually large eggs, and inadvertently discovers a mysterious underground world where dinosaurs still roam.