While Scrat inadvertently causes the break up of Pangaea, Manny and Ellie are forced to deal with the trials and tribulations of their teenage daughter Peaches, who has trouble fitting in with her peers. Ellie tries to support her daughter, but Manny becomes exceedingly over-protective. Meanwhile, Sid’s family returns, but only long enough to drop off the elderly Granny before abandoning them both. Shortly after, a sudden continental break-up separates Manny from The Herd. Trapped on a moving chunk of ice with Sid, Granny, and Diego, Manny has no choice but to ride out the current. Meanwhile, a giant land shift encroaches on Ellie, Peaches, and those remaining on land, causing them to make their way towards a land bridge.
Meanwhile, Scrat, in a subplot, finds an acorn that has a treasure map on it that directs him towards an island. After violent weather pushes them further away from land, Manny’s group is captured by a band of pirates sailing on a floating iceberg led by a Gigantopithecus, Captain Gutt, who attempts to press them into his crew. When they refuse, Gutt tries to execute them, leading to their escape, which inadvertently cause the ship and food supplies to sink. Gutt’s first mate, a female sabretooth named Shira, joins them after she is left for dead.