Plot
In 1959, Sammy, a green sea turtle, hatches on a deserted beach in Baja California and is caught by a seagull while trying to defend himself by spitting in the seagull’s eye. He manages to escape along with another hatchling sea turtle named Shelly, who was also caught by another seagull. After Sammy wakes up from his slumber, the waves start coming in and push the raft he’s on into the water, carrying it away with him still on it. However, Sammy, who manages to recover from his injuries, doesn’t mind being carried away and decides that this is the first step of the beginning of his journey.
The day after he hatches, Sammy befriends a leatherback sea turtle named Ray, who also hatched the day before. Ten years later in 1969, Sammy and Ray have almost grow up together, traveling around the ocean on their raft. One morning, Ray takes Sammy underwater and introduces him to his newfound friend Slim, the day octopus, but they get forced to take shelter from an oil spill caused by an oil tanker shipwreck. As Sammy and Ray grow more prominent and the raft begins losing parts, it suddenly collapses, leaving Sammy and Ray without their home. While they argue, Sammy, Ray, and hundreds of fish are caught in trawler nets and separated. Hours later, Sammy is thrown back into the sea unconscious but gets saved by a dolphin.
Sammy makes it to shore and, the next morning, finds himself in an enclosure, taken in by hippies led by a woman named Snow and a French cat named Fluffy. Eventually, Sammy shares the enclosure with a larger turtle named Vera and brings her into the enclosure, thinking that Sammy and Vera should mate. However, since Sammy still has feelings for Vera is way too old for him, the two sea turtles have a platonic relationship instead. On Christmas 1969, everyone, including Fluffy and the turtles, was all celebrating the holiday together on the beach. As a present for him, Snow paints a peace sign on Sammy’s shell and she makes him their little peace ambassador before wishing him a merry Christmas. Sammy was at first confused about why Snow did it since this is his first Christmas, but he starts to like the marking on his shell as both a present and as a symbol of peace for him. Some more time passes, Vera is released back into the sea by the hippies when they thought she and Sammy are unable to mate. But not long after that, the unauthorized hippies are evicted from their beach by the police, leaving Sammy behind due to Fluffy's tricks.
Sammy returns to the ocean and gets rejoined by Vera. On a food search, Sammy and Vera rescue a female turtle, who turns out to be Shelly. Sammy asks Shelly if she ever gets bored just drifting, going around in circles, and asks if it would be great to travel around the world. He also reveals to her that there's a lot more than these waters than they first thought and he wants to see the ice oceans and strange islands he heard from the humans and he wants to see them. He even mentioned something about a secret passage and asks Shelly if she wants to come along with him, which she agrees since she really likes him and wants to travel around the world with him.
And so, the journey for both Sammy and Shelly have begun and they meet several sea creatures along the way to search for the secret passage. They eventually travel all the way to the Panama Canal where they assume the secret passage is close. After they bravely protect themselves from a school of piranhas, an eagle captured Sammy and took him to its nest where its chicks are about to eat him. Sammy manages to defend himself from the chicks, but only to hear a chainsaw buzzing below him and before the tree falls down, Sammy notices a ship nearby heading toward a place in the distance so after he safely back into the water, Sammy and Shelly follow the ship and they made it to what they assume is the secret passage. When the pair is about to get through it, they unintentionally get themselves separated as they try to pass a lock.
Sammy, thinking it is his fault he lost Shelly, feels depressed and heads back to the ocean where he swims past a bale full of happy sea turtle couples. While swimming past the couples, he met an elderly turtle couple who happened to encounter Shelly which makes Sammy feel with relief that Shelly is still alive and she is heading south to the ice oceans to search for the secret passage. Sammy follows the trail in the hope he’ll see Shelly again and along the way, he encounters a ship where the passengers are tossing down various junks into the ocean. However, Sammy is too close to the ship that two passengers toss down a refrigerator which causes Sammy to climb onto it as a boat.
Sammy travels all the way to Antarctica where he encounters a whale and he asks her for some help. However, the whale accidentally draws attention to a ship full of whalers with one of them fires a harpoon at her, only for the whale to dodge and the harpoon hits the refrigerator Sammy is on instead. Sammy, who is freezing in the water, ends up drawing the attention of a group of Greenpeace workers who found him and picked him up to their ship.
Sammy, who is recovering from frostbite, is being taken by the worker to a lab and he is now placed in a room of the ship. While on his way to the room, he encounters Shelly inside a cage who’s also trying to recover from frostbite. Once the ship makes it to Monterey, California, Sammy is transported to the Monterey Animal Rescue Center and he is placed inside a pen. There, he reunites with Fluffy who apologizes to him for lying to him and he defends himself that he was jealous at that time. He also tells Sammy that Snow and the hippies he knew from the beach are now working for the rescue center. Sammy looks at the window and sees that a few workers are about to release Shelly back into the ocean which causes Sammy to panic and wants to get out of the pen to see her right away. But before Fluffy can open the pen door to get Sammy out, Snow arrives in the room and she was surprised to see Sammy again after all these years and that Sammy has grown up the last time they saw each other. She tells him that she’ll have to tag him first before he’ll be released back into the ocean.
Soon after Sammy was released back into the ocean, two female leatherbacks ask Sammy to help a trapped turtle in a container. His rescue is none other than his old friend Ray. With help from Ray's partner, Rita, Sammy explores a shipwreck and starts exploring inside it before he finds Shelly flirting with another turtle. Rita reveals that a turtle named Robbie is only a playboy. To win Shelly's heart, Ray enlists the help of a toothless great white shark so Sammy can stage a rescue, but Shelly doesn’t mind being part of a fake rescue and she gets together with Sammy again even after the incident at the Panama Canal. And because the love between Sammy and Shelly is so strong for each other, the two get married at the shipwreck with the other sea turtles attending their wedding. The newly-wedded couple both swim away together after the ceremony so they could continue their journey around the world.
The movie ends as in 2009, Sammy and Ray, now both a new grandfather to their respective grandkids, both watch Sammy’s newborn turtle hatchlings get across the street from their nest so they could get to the water. Just then, Sammy heard a sound of his youngest grandson crying for help in the nest and sees him struggling to get out. Sammy, knowing exactly how his grandson feels about being the last to hatch out of the nest and having trouble getting out, helps him out and watches him follow his siblings to the water.
