Sonic 2: The Hedgehog

Eight months after being defeated and banished from Earth to the Mushroom World by the speedy blue hedgehog Sonic, the evil Dr. Ivo Robotnik is trying to find a way to escape the desolate planet to which he was previously banished. He begins sending out distress signals into outer space, which are quickly picked up by a group of alien hunters who appear through a ring-shaped portal to his location. They are quickly knocked unconscious by the numerous traps set by the mad scientist. However, before they reach the portal, an anthropomorphic red echidna emerges and asks Ivo where he got the blue thorn he's holding. Ivo bluntly tells him that he can help him reach the source of the thorn if he wishes, but only on the condition that the red echidna helps him escape the Mushroom World.

Meanwhile, now living with the Wachowskis and eager to prove his worth as a hero, vigilante, and righteous man at their expense, Sonic tries to use his powers to help others in his new life, though he has little success as his recklessness gets in the way. During a fishing trip, Sonic argues with Tom about it after learning that he snuck into Seattle and destroyed an entire city block while stopping a robbery, but Tom replies that it's not yet time to prove his worth and that when the need arises, that will be the time to act. A few days later, Tom and Maddie agree to leave Sonic alone in the house while they go on vacation for the weekend for his sister-in-law Rachel's wedding in Hawaii. When they leave, the hedgehog has a great time until nightfall, but his alone time is interrupted when the evil Ivo unexpectedly breaks into the house. At that moment, Sonic tries to attack him, but ends up fighting Ivo's new ally, whom he introduces as Knuckles. During the fight, the blue speedster hedgehog is overwhelmed by his opponent's immense strength, and Knuckles tells him he plans to avenge his tribe of echidnas, the Pachacamac, which was wiped out by Longclaw's crimes. But before he can finish him off, a police patrol car bursts into the garden and runs over Knuckles, knocking him out for a moment. Sonic takes advantage of the situation to escape.

At that moment, the patrol car driver introduces himself as a two-tailed, yellow-orange anthropomorphic fox named Miles "Tails" Prower, a robotics genius who has been watching him ever since he caused the electromagnetic pulse that shut down the entire Pacific Northwest. Miles is a huge fan of Tails, even idolizing him, and has come to warn him about the threat of Knuckles, who wants to know the secret location of the Master Emerald. Their meeting is suddenly interrupted by Knuckles, who is hot on their heels. To escape the red echidna, Tails causes the patrol car to veer off a cliff. While Knuckles clings to the mountain with his fists, the two friends are propelled into the air by Tails' ability to use his tails like a propeller. Finding refuge with Tom's police officer friend Wade, the duo discovers a message on Sonic's world map recorded by his deceased guardian, Longclaw. She tells him she has entrusted him with the task of protecting the Master Emerald and gives him clues that will lead him to a hidden temple in eastern Siberia. Sonic convinces his new friend to join him on his mission, promising to protect him. After arriving at a mountain establishment and putting on a dance performance to avoid being killed by the diners, Tails is thrilled when Sonic refers to him as a friend. He explains how seeing Sonic inspired him to leave the village where he was considered odd because of his two tails to help him, and Sonic tells him he's glad to have him by his side.

Meanwhile, Ivo and Knuckles reunite with Agent Rock, who has been waiting for their return in a hideout café, plotting to steal the emerald for himself at Ivo's expense. The scientist agrees to help the echidna with his revenge plan. Ivo then brings a space station down to Earth, changes his costume, and assembles an army of robots and drones to hunt down his enemies, now operating under the alias Doctor Eggman. Once at the temple, Sonic and Tails discover the history and origin of the Master Emerald: Knuckles' ancestral tribe, the Pachacamac, created the seven Chaos Emeralds and kept the coveted emerald in their possession. This emerald possesses the power to build and destroy entire civilizations, which they intended to use to launch a universal invasion. However, their main enemy tribe, the Nocturn (Long Claw's tribe), invaded the Pachacamac homeland to seize the emerald and protect it from falling into the wrong hands, successfully achieving their goal. They also discover an old compass that points to its location, but are interrupted by the arrival of Eggman and Knuckles. To escape, Sonic slides down the mountain using a piece of a drone he destroyed, while Tails takes to the air. Knuckles and the drones pursue him, causing him to lose all his rings in the process.

During a break in the fight, the red echidna tells the blue speedster hedgehog that the reason for his revenge is because, hours before he was teleported to Earth, the warriors of his Pachacamac tribe were enlisting to hunt him and Longclaw. At that moment, a young Knuckles, who also wanted to join the hunt, was stopped by his father, who told him that his time to shine hadn't yet come and that it would soon. For now, he had to wait at home until the tribe returned from the hunt. Unfortunately for the young red echidna, those were the last words his father ever said to him. After that, he never saw him or the rest of his Pachacamac tribe again, leaving the young red echidna an orphan. At that moment, Sonic tells him that they both lost everything that day, leaving his opponent somewhat confused. Tails takes advantage of this to try and catch the echidna warrior, but fails. Sonic throws him the compass to escape. However, Eggman intercepts it mid-flight and knocks Tails unconscious with his missiles. To make matters worse, this causes an avalanche, endangering the duo while the villains escape.

In danger and without his rings, Sonic calls Tom in the middle of the ceremony and asks him to open a portal to reach him. This interrupts the wedding, as the magic rings were mistakenly used for the couple, and when the portal opens, the duo and some snow flood the altar. After giving them a summary of what was happening, things get complicated when the guests and Rachel's fiancé, Randall, reveal themselves to be secret agents of the national security unit, "GUN," created after the San Francisco incident. They explain that the wedding was a trap to capture Tom, Tails, and Sonic, but they are rescued shortly after by Maddie. Rachel confronts Randall and the general, and the blue speedster hedgehog heads to the Master Emerald temple, leaving Tails in the care of the humans, wanting to ensure he doesn't get hurt.

Meanwhile, Eggman and Knuckles raise an ancient temple containing the Master Emerald from the depths of the sea and navigate a labyrinth of deadly traps to finally reach the Emerald alongside Sonic, who arrives just in time to stop them, though Eggman had secretly planned to betray Knuckles seconds before. Another battle ensues between the speedy blue hedgehog and the red echidna, and before he can finish him off, Sonic makes Knuckles realize that Eggman was only using him. When the mad scientist manages to steal the Master Emerald, he teleports to Green Hills, and the town begins to collapse under floodwaters. Sonic saves Knuckles from drowning when a boulder falls on him during the flood, and before he too is submerged, the echidna returns the favor. After discussing the words Tom said to Sonic, the rivals agree to team up to stop Eggman's plans and are rescued by Tails, who arrives flying in a plane that was used for the ceremony.

Back in Green Hills, Eggman arrives and frees Agent Rock, who was being interrogated by Wade at the café. GUN forces arrive to arrest him, but the scientist has already absorbed the Emerald Crystal and gained the power to manipulate time and reality at will. Leaving the café and easily defeating the military, he uses parts of their vehicles and buildings to create a giant robot in his own image, the Death Egg Robot. Meanwhile, Sonic, Tails, and Knuckles arrive and fight the giant robot and the drones destroying the city, but they are still outmatched in weaponry and power. Then the three devise a plan using Sonic as bait, but while Tails and Knuckles secretly infiltrate the robot and steal the Master Emerald from Eggman, the speedy blue hedgehog is too exhausted to continue fighting, and Eggman seizes the opportunity to kill him. However, Tom and Maddie appear at the wheel of a car and rescue him at the last second, but during the escape the car is destroyed and the Master Emerald shatters, losing all its energy and revealing the source of its immense power: the Chaos Emeralds. These merge with Sonic's body just before he is crushed, giving him a new power and a new transformation known as Super Sonic.

With this newfound power, the super-speedy hedgehog successfully destroys the Death Egg Robot, much to Eggman's dismay. Eggman declares to Sonic that they will never be friends as he falls to his apparent death. Out of danger and after restoring Sonic to normal, Knuckles manages to repair the Master Emerald and vows to protect it alongside Sonic and Tails. Later, the Wachowski family grows with the addition of Knuckles and Tails. While they play a game of baseball, Sonic touches Tom's heart by accepting him as his father. Afterward, they all leave in Tom's car, and Sonic returns to retrieve the Master Emerald, which they had forgotten in a cooler on the field, and takes it with them.

In a mid-credits scene, GUN forces are exploring the wreckage of the Death Egg Robot in search of Eggman. Among them is the surviving and infiltrated Agent Roca, but they find no trace of him anywhere in the area, though they also doubt that Eggman survived the battle. At that moment, a soldier informs her general that while erasing all the information about Eggman from the first time, they discovered some files that mention a top-secret, unknown project. This leads them to an old, abandoned prison containing an experiment over 50 years old, known as Project Shadow. Moments later, the scene shows a mysterious cryogenic capsule containing an anthropomorphic black hedgehog with red stripes, locked inside the old military prison. Shortly after, the capsule mysteriously deactivates, and the black hedgehog awakens from its long cryogenic sleep.