Unlikely prehistoric pals Manny the mammoth (Ray Romano), Sid the sloth (John Leguizamo) and Diego the sabre-toothed tiger Dennis Leary are cast into a climate catastrophe, when the cooling glaciers divide their world in two.
The trio are divided from the rest of their friends and family, including Manny's panicked teenage daughter Peaches Keke Palmer, and strong sea currents soon take them far out to sea. After discovering the stowaway from hell - Sid's cranky Granny ]Wanda Sykes - the trio are hijacked by the evil pirate ape Captain Gutt (Peter Dinklage), who's determined to prevent them from reaching their families. Will they ever make it home?
There's still plenty of warmth in this frosty franchise, which shows no sign of melting as it approaches $2.8 billion in worldwide box office takings. While the animation and story are as fun as ever, it's largely down to the charismatic cast, the irrepressibly spirited Sykes in particular. Other familiar names include Nick Frost, Jennifer Lopez and a returning Queen Latifah.
Plus, the hugely popular rodent Scrat is back: will he ever get his hands on that elusive acorn?