Picking up from the previous episode...
It's the morning after Lapis Lazuli left Steven and the Gems on the beach. They are home now, on the porch. Steven protests against being grounded. Pearl insists he is; Garnet clarifies it's because he disobeyed a direct order. Amethyst, serious and upset, lifts a shovel and tells him that they're going to bury him alive until he's learned his lesson.
Before the conversation can continue, a winded Greg bursts through the door and tells the Gems they need to come see something.
They arrive at the beach, discovering that the ocean is completely gone, leaving nothing but sand, beached vessels, and junk as far as the eye can see. Mayor Dewey is in a right tizzy, upset at the loss of vital summer revenue if people won't come to a Beach City that lacks a beach. All the people Steven has met so far in the season are gathered on the beach; Fryman worries that he'll have no customers. So does Kofi Pizza. Lars laments that the girls won't come if there's no beach. Mr. Smiley expresses concern that no one will come to Funland.
Steven declares this his fault, and packs his backpack to set out on a quest to find Lapis, and ask her to give back the ocean. Greg immediately volunteers to come along, despite usually staying behind on Gem missions. Connie says she's coming as well, and the Gems naturally insist on joining Steven's quest, ungrounding Steven in the process for stepping up to take responsibility and trying to find a solution.
Steven and Connie ride Lion. Greg drives with Garnet sitting in the shotgun seat, and Amethyst and Pearl crammed in the back. To pass the time, Greg puts in a hard rock tune he calls one of Rose's favorites. Garnet bails out of the van without a word upon hearing it and spends the rest of the ride reclining on the van's roof. In the course of conversation, Steven mentions that he never thought they'd have to fight a Gem. Pearl says they've been fighting Gems all along, and tries to explain it delicately. Amethyst blurts out the truth: that all the monsters they've faced used to be sentient Gems like Garnet, Amethyst, and Pearl; and that the Gems have been bubbling them for want of a way to restore them, but being unable to do so.
After driving all day, Steven and company finally find where the ocean has gone: it has been turned into a semi-solid pillar that reaches up into the sky. Steven tries to talk to Lapis, but she doesn't want to talk. She tells Steven he's one of them, and implies that makes him an enemy. But because of her gratitude for his help, she gives him a chance to leave.
Steven attempts to convince Lapis that they're summer fun buddies, but she will not be moved. She again demands to be left alone, but Steven says they won't go until she gives back the ocean. Lapis retaliates by generating aquatic reflections of Steven, Garnet, Amethyst and Pearl.
Garnet prepares for battle, warning her partners to not get separated when Reflection Garnet punches her far across the ocean floor. The battle is joined! Pearl warns Steven and Connie to stay back. Lion steps up to guard them, then fights Reflection Steven, to no avail. The Reflection Gems, being water, are almost impossible to beat as they re-form themselves after any attack the Gems throw at them. When Lion is thrown into Greg's van, he cries out in dismay. Connie and Steven rush into the fray shouting, "Revenge!" Lapis takes them easily, encasing the children's heads in water bubbles. Greg saves them by driving his van through Reflection Steven, dissipating him.
Lapis' Steven-construct water-blasts Greg and his van into the air. It comes down on its nose. Steven rushes to his father's side, only to discover Greg has broken his leg and is out of the fight. This is the last straw. Steven Universe steps forward and shouts to Lapis that he doesn't want to fight anymore. The constructs continue to attack, but Steven calls his shield and repeats:
The construct dissolves against the shield, and Steven's statement of intent echoes across the battlefield, destroying the other reflection constructs as well. Fight over, Steven declares that he is coming to the top of the tower to see Lapis and asks her not to drown him. He steps into the tower of water, and a hand construct lifts him to the tower's apex: the literal edge of outer space.
Lapis demands to know what Steven is doing, but he reverses the question on her, insisting that Gems should all be friends. Lapis chastises him for his naiveness over the Crystal Gems; in her eyes, they don't care about other Gems as much as they care for the Earth, a planet she never believed in. She looks sadly at the stars and indicates she was only using the ocean to stretch into space far enough to go home. Steven points out that the ocean is an important part of his home and that's why he's there to get it back. Lapis laments that if her gem weren't damaged, she could try to get home on her own. Steven tells her he has healing powers, and heals her gem. From the gem, water wings spread and Lapis' eyes are no longer reflective; she's completely healed! She thanks him and leaves flying. Seconds later, without her magic to hold it together, Lapis' ocean tower comes apart, and Steven falls back toward earth. Connie and Lion pull a mid-air portal rescue, then Steven bubbles the Universe van and the others. They return to Beach City triumphant, aside from Greg's broken leg and totaled van.
As everyone in Beach City rejoices, Garnet and Pearl muse about what may come to Earth, now that Lapis has left to go home. Steven looks skyward.
We Iris Out on a faraway star in the sky.
- A Good Name for a Rock Band: A visual example. Greg's reaction on seeing that Lapis has turned the entire ocean into a giant space needle stretching into the heavens is to say that he's just had the best idea for an album cover.
- Absurd Altitude: Lapis's column of water stretches far above the Earth's surface, and she was hoping to stretch it far into space in an effort to reach home.
- Ask a Stupid Question...: This exchange:Mayor Dewey: What's going on here?
Garnet: The ocean is gone, obviously.
- Asteroids Monster: When Pearl splits her water clone in half vertically with her spear, it forms into two Water Pearls.
- Antagonist Title: Once more, Ocean Gem is referring to Lapis.
- Batman Can Breathe in Space: It's already been established that the gems don't need to breathe; but Steven does. Despite that, in this episode, he has no trouble breathing at an altitude at which there should basically be no atmosphere.
- Book-Ends: In the second episode of the first two aired, "Laser Light Cannon", Greg's van ends up damaged on the beach from being washed out to sea. In this episode, which was originally meant to be the last of the first season, Greg's van ends up badly damaged and back on the beach after the ocean returns.
- Steven's shield from "Gem Glow" makes a return. This time he consciously summons it.
- Steven's Bubble force field from "Bubble Buddies" and "Lion 2: The Movie".
- Connie's parents said in "Mirror Gem" that she couldn't hang with Steven that day, but could spend the entire next day with Steven, and that's exactly what she does.
- In "Steven and the Stevens" one of the Stevens travels to a desert with deserted boats, which eventually happens in this episode.
- Car Fu: Greg rams the Steven construct with his van as it's trying to drown Steven and Connie.
- Caustic Critic: Garnet has a...less than tactful way◊ of showing Greg what she thinks of his music.
- Continuity Nod:
- Pearl's note that she hates fighting herself may be referencing her hologram-self from "Steven the Sword Fighter".
- While fighting against her clone Amethyst transforms into her Purple Puma persona from "Tiger Millionaire".
- Pearl knowing how to drive was shown in "Arcade Mania".
- In "Lion 2: The Movie", Connie said Steven obviously has some "magical destiny". When she sees Lapis's water tower, she remarks "That's some magical destiny stuff, right there."
- After his van is totaled Pearl tries to comfort him with little luck by referencing his catchphrase from "Laser Light Cannon".Pearl: What's that you always say about the pork chops?
- Determinator: "I'm gonna bring the ocean back, or get really thirsty trying."
- Dual Wielding: When Pearl's copy splits into two, she summons a second spear to fight them off.
- Flashback: As Pearl and Amethyst explain that every monster they've fought used to be a Gem, the scene flashes back to show every monster they've fought and bubbled in order, right up to the last one in "Monster Buddies".
- Growing Wings: After Steven heals her cracked gem, Lapis' liquid wings are restored and she leaves Earth, in an attempt to go home.
- Healing Hands: Steven uses his magic spit to restore Lapis.
- Inelegant Blubbering: Mayor Dewey at the idea of losing all the summer tourist dollars.
- Iris Out: Over a distant diamond-shaped star above the temple: likely the same one from Mirror Gem. The iris itself briefly changes from a five pointed star to a four pointed one in order to outline said distant star.
- Kick the Son of a Bitch: Tired of Lars talking out loud his plans of summer flirting, Sadie pushes him into the recently-returned water.
- Let's Get Dangerous!: After Greg gets a broken leg from the Steven copy launching his van into the air, Steven loses his temper and insists that he doesn't want to fight. When the Steven copy tries to press the issue, Steven summons his shield and releases a pulse which destroys all the copies.
- Literal-Minded: Amethyst assumes "grounding" to mean they have to bury Steven in the ground.
- Making a Splash: Lapis Lazuli has extraordinary water powers: enough to drain an ocean to shape a quasi-liquid tower to the stars.
- Mirror Match: Steven and the Crystal Gems face off against water clones of themselves created by Lapis.
- Multi-Part Episode: With "Mirror Gem."
- Nice Job Breaking It, Hero!: While he had his reasons, and it wasn't really the wrong choice, the immediate cause of the disaster in this episode is Steven releasing Lapis without asking enough questions about who she was and what she'd do after she was freed. Though part of the blame can be laid at the feet of the Gems, who kept Steven in the dark instead of saying "We're afraid that this artifact might be dangerous, or contain a monster," instead of insisting they knew best and trying to take away Steven's new friend.
- Nigh-Invulnerability: Until Steven summons his shield, the water clones prove to be unstoppable. The Gems can't destroy them because they just reform if damaged, and they can match the Gems blow for blow.
- No Endor Holocaust: The potential damage caused by the retreat of the entire ocean for at least a day is mostly ignored, as are the consequences of the ocean falling back to earth afterwards.
- Oh, Crap!: When Lapis begins her assault on the Gems, Pearl's shout for Steven to run is chilling.
- Papa Wolf: Don't mess with Steven when Greg's around. He may not have powers, but he has a van.
- Pummel Duel: Garnet and her water clone just go at each other with Rapid-Fire Fisticuffs.
- Powerful and Helpless: Lapis can literally move an ocean, but with her gem cracked, she still can't leave Earth, much less reach Homeworld.
- The Reveal: All the monsters the Gems fight are really corrupted Gems. The Gems are also revealed to actually alien in origin.
- Sci-Fi Writers Have No Sense of Scale: Lapis's water pillar is able to reach out into space, but not even as far as the moon. If she really focused all the ocean's water into a pillar of that size (judging from the scenes showing the Earth from above, she did), it should be much taller than thatmath —so much that creating it in a day would require most of the water to have traveled faster than the speed of light. Although even that wouldn't be anywhere near far enough to reach another solar system as Lapis wanted. Conversely, making a pillar of the shown size would not even reduce the ocean's volume enough to counter the last year of melting ice caps in real world Earth.
- Screw This, I'm Outta Here!: Garnet's reaction to Greg's music is to jump out of the van.
- Season Finale: This episode ends the first half of Season 1, referred to as Season 1A by both fans and crew.
- Sequel Hook: Lapis gets to go home, but the Gems seem worried about what might find its way back to them.
- Shooting Superman: Steven uses a super soaker on his water copy. Understandably, this is useless.
- Skewed Priorities: The citizens of Beach City are only worried about the ocean's disappearance affecting their businesses and summer vacations rather than the global ecosystem.
- Sleep Cute: Connie sleeps on Steven's back as they're riding Lion.
- Star Scraper: Lapis' ocean tower, made in an ill-conceived attempt to lift herself back to her homeworld. She acknowledges that it wasn't the best plan, but with her gem damaged she can't do any better.
- Stealth Pun: After Steven heals her, Lapis Lazuli grows a pair of water wings to fly away with.
- Take My Hand: Connie and Lion as Lapis' tower begins to revert to salt water and Steven begins to fall from literally the edge of the atmosphere. Also the title of the music track in that scene.
- There Is Another:
- Not only did the revelation of Lapis' very existence in the previous episode prove that Garnet, Amethyst, and Pearl weren't really the last of the Gems, but in this episode, her strong desire to go "home" heavily implies that there are many more Gems out in space, with them not really being near extinction at all.
- The revelation that the monsters they've been fighting all of first season are corrupted gems shows that Garnet, Amethyst, and Pearl aren't even that close to being the last Gems on Earth; they're merely the last sane gems on earth.
- Thirsty Desert: Invoked by Steven: "I'm gonna bring the ocean back, or get really thirsty trying."
- Took a Level in Badass: Steven deliberately summons both his regular and bubble shields in this episode, and his healing powers seem to work at will or are always active. Impressively, his regular shield destroys all the water constructs Lapis made to fight the Gems, when before this the Gems couldn't beat their copies.
- Trailers Always Spoil: Steven summoning his shield was being used in promotional material weeks before this episode.
- Vagueness Is Coming: At the end, Garnet and Pearl wonder what could be in store for them when Lapis makes it back to their home planet.
- Visual Pun: Lapis flies away with water wings.
- Wham Episode: All those creatures the Gems have been fighting, destroying, collecting their central gems? All of them are of the same species as the Crystal Gems, and were once as humanoid as Garnet, Amethyst, and Pearl are, but somehow were corrupted and turned into monsters. And the setting got expanded to include the depths of space, where there are presumably more Gems.
- Wham Line:Steven: Gems shouldn't fight each other...
Pearl: We're always fighting Gems, actually.
Pearl: Oh, how do I put this? All Gems aren't necessarily...good, and-
Amethyst: All those monsters we fight used to be just like us!
- Would Hurt a Child: Despite Connie and Steven being comically unthreatening to Lapis Lazuli's water clone, it engulfs their heads in water, suffocating them until Greg runs it over with his van.