After a short hiatus, "Summer of Steven" started airing on July 18, 2016, and concluded on August 12, 2016. This was a special event that lasted four weeks. The season concluded on August 10th, 2016 with the episode "Bubbled".
When Steven learns that he can possess his creations (the Watermelon Stevens residing in "Super Watermelon Island") through his dreams, he finds that Lapis Lazuli has lost total control over Malachite at the bottom of the ocean and is now running rogue in Mask Island. The Crystal Gems leave Steven and a very concerned Peridot, who is stressing that the Cluster has begun to generate small tremors, at the barn. Steven falls asleep again and possesses another Watermelon Steven. He witnesses the Crystal Gems' transformation into Alexandrite and their battle against Malachite, but the Crystal Gems' fusion is too weak. In response, Steven gathers a Watermelon Steven army to rebel against Malachite and is able to distract her, allowing Alexandrite to pierce her with an arrow.
Malachite unfuses into Lapis and Jasper as the gems celebrate. However, an earthquake hits the island, signaling the imminent danger that is the Cluster. The Island splits and an unconscious Jasper falls into a crack in the ground. The Gems tell Steven to wake up and destroy the Cluster with Peridot and the drill since they are too far away to make it back in time. He does so in "Gem Drill", where the two activate the machine and start drilling towards the Cluster's coordinates. After another gem mutant attack, Steven realizes he does not want to hurt the Cluster or any of its Gems, but Peridot is determined to destroy it, especially once they make contact.
However, when the drill hits the Cluster, Steven starts to feel its pain. This culmination of feelings causes him to enter the Cluster's psyche. He learns that the Cluster shards do not want to form but instead want to feel whole. In response, Steven talks them into enjoying each other's company and bubbles the entire Cluster, with the help of the shards themselves. Steven and Peridot return to the surface to find the Gems with an unconscious Lapis, who wakes up in "Same Old World". Lapis realizes she has no home anymore, as she hates Earth and can't go back to Homeworld.
Steven then tries to convince her that she can stay on the Earth. With Lapis, the two fly around the world to seek a place for her, but when Lapis sees the Galaxy Warp, she becomes upset. She tells Steven the story of her abandoning on Earth after being mistaken for a rebel Crystal Gem and placed in a mirror to serve as a respondent. She was left and broken within the hurry of the evacuation, but Steven convinces her that she can stay on Earth and learn to love it. However, when she learns that Peridot has reformed and has decided to live in the barn too, she becomes woeful and gradually bitter toward Peridot since she had used her much her imprisonment by Homeworld. In "Barn Mates", Steven helps Peridot find ways to be friends with Lapis, with many of his proposals and activities failing until Steven talks to her and reminds her of a common goal they have. A Roaming Eye suddenly appears, sent by Homeworld to capture Peridot, but Lapis destroys it to protect her, signifying her warming up to Peridot. But from the vessel, a troop of ruby soldiers appears searching for what seems to be Peridot and, in "Hit the Diamond", Garnet unfuses so that Ruby can infiltrate with the troops and lead of the Earth. However, in a twist, they end up engaging in a game of baseball that will decide if they leave or stay, which the Gem team, disguised as humans, ultimately wins, but Ruby and Sapphire's will to stay together ends up screwing their cover when they fuse. The rubies question the Gems, but when Peridot gives herself in, they claim to be looking for Jasper, who Steven lies about, telling them she's on Neptune to keep them away.
Now that everything is clear, the main Crystal Gems head back to the temple in "Steven Floats", where he uncovers a new power: floating. However, he cannot control it and stays stranded in a very slow descend, when he so wanted a fresh donut the next morning. The Gems spend the night with him leading him to finally realize how to descend: to think of happy thoughts that will alter his emotion and in the end, he is able to reach the floor and eat the donut that awaited him. When Sour Cream's dad, Marty, comes back to meet with Greg in "Drop Beat Dad", Steven helps them put on a DJ show with Sour Cream, but in the end it's revealed that Marty was just doing it for his product endorsement. Yellowtail, Sour Cream's stepdad, stands up to him, leading Marty to leave, right after giving Greg a check of 10 million dollars from royalties of selling his song for a jingle. In "Mr. Greg", Greg and Steven decide to invest on a trip to Empire City, and Steven brings Pearl along so she and Greg can mend their broken relationship. In the end, Steven is able to unite the two by showing how much they having in common and the two come out of Empire City with a brand new friendship. In "Too Short to Ride", when Steven, Amethyst, and Peridot cannot ride on a rollercoaster due to their height, they explore the art of shapeshifting, revealing that Peridot is unable to shapeshift due to a lack of resources on Homeworld. However, in an intense moment when Amethyst confronts her about her obsession with technology, she discovers that she has the power to control metals with her mind. In "The New Lars", Steven's psychic powers play a trick on him, and he wakes up in Lars' body. Steven learns more about Lars' life, but ends up causing trouble when he decides to confess Lars' love for Sadie. This caused her to get angry, and she yelled at him, showing Steven what kind of relationship she and Lars have, and her true feelings. When he learns he had been possessed by Steven all day, Lars becomes furious, though later on in the day, Lars and Sadie make up.
In "Beach City Drift", with a large majority of his money left, Greg decides to invest on his dream car, but when Kevin shows up, it's Stevonnie's time to shine, and they decide to take revenge on Kevin for being pushy by crushing him in a car race. However, Steven and Connie realize that obsessing over Kevin is pointless and decide to enjoy the ride for themselves. In "Restaurant Wars", Steven accidentally creates a war between The Fish Stew Pizza and The Beach Citywalk Fries. Steven, Kiki, Jenny, Peedee, and Ronaldo team up to stop the conflict, succeeding by creating their own restaurant, forcing the restaurant owners to reconcile. But the trouble in the Pizza family isn't over when, in "Kiki's Pizza Delivery Service" Steven helps Kiki "survive" her cheesy nightmares that have been giving her insomnia. In the end, it turns out the nightmares are a product of Kiki's over-work and of her inability to say no to covering Jenny's constant bail-outs at work, and in the end, she learns a valuable lesson about self-worth.
In "Monster Reunion", Steven's healing powers return, and Steven's first thought is to keep his long-made promise and try to find a cure for the Corrupted Gems. He decides to first try to heal Centipeetle, his old friend, but the cure doesn't work fully, and she remains half-corrupted. However, the two attempt at communication and Steven learns of Centi's tragic backstory, how she was a pilot of Homeworld's ships that was left behind during the panic of escaping Earth and got caught within a mysterious weapon from the Diamonds that corrupted her and many others. However, her form starts to destabilize, and Steven has to discover her ultimate wish: to return back to her crew, in the Old Warship, back in her corrupted for form. When Steven decides to take Lapis for a trip in Greg's rented boat, in "Alone at Sea", things get tense when Lapis starts to realize that she's strangely missing Jasper and being Malachite with her, and get even tenser when out of the sea pops Jasper, who's been following them, just to convince Lapis to fuse back with her, now enamored with the act of fusing, and mostly, it's power. However, Lapis refuses, and Jasper is sent back to the sea via Lapis' hydrokinesis, when she attempts to attack Steven, blaming him for Lapis' refusal. Lapis, Steven, and Greg fly off into the sea as the boat sinks, disappearing into the sunset.
Later on after that sailing trip, Steven helps his dad out at his car wash, It's A Wash, and Steven asks Greg how he came to own the car wash. Greg tells a story about how he came to babysitting Vidalia's son, Sour Cream. Greg and Rose Quartz meet up, and when Greg leaves Sour Cream with Rose for a few minutes, Greg comes back to find Sour Cream gone. Greg finds Rose and saves Sour Cream from falling off an amusement ride at Funland. Rose learns a valuable lesson about human culture.
In "Gem Hunt", Steven, Connie, and Pearl go on Connie's first mission, to locate corruption gem activity at the Great North. When the two kids separate from Pearl to find one of two monsters that come in their way, they follow clues to locate their monster, but when they come across it Connie freezes, but is successfully able to contact Pearl for help. However, Jasper appears instead, to retrieve the two gems. Back at home, in "Crack the Whip", Amethyst is in charge of Steven and Connie's sword-training when Pearl leaves to find Jasper. However, they spend a day of fun instead, until they're interrupted by Jasper, who has started to build a monster army, and Amethyst attacks. However, she's defeated by Jasper, who not only reminds her of her shortened and "useless" physique, but also poofs her, leaving for Steven and Connie to fuse and chase Jasper away. However, when Amethyst reforms she is upset about Jasper's words and that Steven is now better than her, so in "Steven vs. Amethyst the two compete in Pearl's supervision, only for Steven to always outrun Amethyst. The two engage in a serious fight, where both are able to come to terms with each other and acknowledge their similarities.
In "Bismuth", Steven accidently pops a mysterious bubble inside Lion's mane, that turns out to contain Bismuth, one of the original Crystal Gems. As they all bond over old times and get updated weapons from Bismuth's weapon-making skillset, Steven is bound to uncover a terrible truth about his new friend. Years ago, Bismuth has created a weapon for shattering gems, and offered it to Rose, who denied such cruelty, and hid Bismuth in a bubble for millennia, lying to everyone about their misguided friend. When Bismuth makes the same offering to Steven, history repeats itself and a fight ensues, poofing Bismuth, only this time, Steven will speak the truth to the gems about everything.
In "Beta", Amethyst is still obsessed with defeating Jasper, though, so Steven takes her to pay Lapis and Peridot a visit, now that they've transformed the barn into an art gallery. However, Amethyst is not impressed and just wants to train, so Peridot decides to show her how much better she is from Jasper by showing her Jasper's Kindergarten, the Beta Kindergarten, that's of mediocre quality. However, there they find that Jasper is indeed the perfect Quartz, analyzing her hole, and Jasper herself, who's taken the Kindergarten as the prison for her army. A fight between her and Amethyst ensues in "Earthlings", where Jasper has no way of being defeated, that is until Steven and Amethyst bond again over their weaknesses, and become stronger, fusing accidently into Smoky Quartz, who easily overpowers Jasper. Seeing no way to win, Jasper desperately fuses with the monster from the Great North, but still, Smoky wins and Jasper is forced to unfuse. However, a strange phenomenon happens and Jasper begins to become corrupted too, until she now longer has conscience, delivering one last speech about Rose's insolence towards their common Diamond, Pink Diamond, before being poofed by Peridot's metal powers and bubble by Amethyst. Arriving back home, they find that Lapis has the Rubies trapped in bubbles because they have returned. In "Back to the Moon", the Rubies demand that they tell them where Jasper is, upon not finding her on Neptune, so Amethyst shapeshifts into her and tricks them once again. Lying about being Jasper, saying she'll stay on Earth keeping the Crystal Gems prisoners, the Gems have to return to the Moon Base so the Rubies can file a report. In there, one of the Rubies, Eyeball, give the gang some first-hand exposition on Pink Diamond, who the base belonged too, revealing she has been shattered by Rose, shocking Steven. However, the Rubies end up unable to file the report and "Jasper" tells them to do it themselves, back on Homeworld. When they leave in their shuttle, they finally find the truth about the ruse when Amethyst can no longer contain the form and so fuse together to fight. Steven outsmarts them though, when he opens the airlock and Garnet and Pearl fuse into Sardonyx, forcing the fusion to leave to open space, taking Steven with them. In outer space, Eyeball finds her way to Steven, who's activated his bubble shield for security, in "Bubbled", and the two act grumpy towards each other, as Steven tries to convince her that he is technically Rose Quartz, upon listening to her desire to meet her. However, when Eyeball's gem cracks in a meteor shower, Steven takes her inside and heals her, making her realize Steven was speaking the truth, attacking him with a shizel to take his gem off and raise in status back on Homeworld. She fails however, and flies off into open space again, as Steven is found by the Crystal Gems, in the shuttle, and helped out. Garnet clears his doubts about Pink Diamond's murder, revealing it was real and it had to be done, which Steven understands.
Season 2 and Season 3 were originally formatted as a single 52-episode season. However, for unknown reasons, Cartoon Network re-labelled the second half of the second season as Season 3, and then split the original third season into Season 4 and Season 5.
Season 3 effectively has 25 episodes – this is due to all of the digital shorts being counted as a whole episode, and the double-length episode "Bismuth" being counted as two separate episodes.
Season 3 has taken the shortest amount of time to air, only airing within the span of about 3 months.