Continuing from where "Destinies Collide" ended, Cassandra reveals what she saw while inside the House of Yesterday's Tomorrow. She had met a disembodied spirit who showed her a vision of her past. From this vision, Cassandra learned that she was the biological daughter of Mother Gothel, who abandoned her on the night she kidnapped Rapunzel. Convinced by the spirit that Rapunzel had been overshadowing her for the entirety of her life, and no longer wanting such a destiny, Cassandra has stolen the Moonstone and declared Rapunzel's destiny as her own. Even though she is confronted by Adira, who ordered her to give up the Moonstone, Cassandra easily repels the warrior away and steals her Shadow Blade. As the Black Rocks cover her, Cassandra escapes from the group, despite Rapunzel's pleas not to cross the line, and severs all ties with them, with Rapunzel devastated over the recent turn of events.
With Cassandra gone, Rapunzel tries to focus on a method of returning home to Corona, while Eugene suspects that she is in extreme denial over Cassandra's betrayal. Just then, the group spots a balloon flying their way, and it is revealed to be piloted by Ulf. With Shorty translating, Ulf informs them that Corona is in danger, and Rapunzel realizes they need to return immediately. With King Edmund and Adira deciding not to accompany them, Rapunzel and the others board the balloon and fly back to Corona.
Upon arriving in Corona, the gang discovers that the kingdom is nearly deserted, save for Feldspar, who is mumbling to himself about a new order from King Frederic to mine unusual crystals. Upon hearing this, Rapunzel and the group head for the castle and meet up with the King and Queen. But to her shock, King Frederic and Queen Arianna have no memory of who Rapunzel is. A moment later, Andrew arrives with the Separatists of Saporia, declaring that Corona will soon be under their control. He also reveals that he has forged an alliance with Varian, who reveals that the Separatists have used a Saporian Wand of Oblivium to erase the memories of the King and Queen. He next reveals his plan to harness the power of the wand and create a synthetic gas that will erase the memories of everyone in Corona, and he has dubbed it "Quirineon" in honor of his father. Deciding that this plan cannot be carried out, Rapunzel leads the charge against the Separatists, but thanks to Varian's chemicals, our heroes are easily outmatched. At Eugene's suggestion, they retreat with the Separatists in hot pursuit.
With our heroes having suffered defeat at the hands of Varian and the Separatists, they try to find a safe place to hide until they can formulate a plan. Just then, Xavier reveals himself along with other citizens that had not left the city. Xavier reveals that the King had ordered all the subjects to the mine to excavate crystals for Varian's minerals. They wanted to rebel against this order, but doing so would be an act of treason. However, Xavier states that now that Rapunzel has returned, they have a chance to save all of Corona. Unfortunately, Rapunzel does not feel confident enough that she can lead them to victory. Xavier promises to give her time to think about it.
While Rapunzel works on a new frying pan to replace the one destroyed in the previous battle, Eugene notices the look of anger on her face and tries one more time to talk to her, saying that she's not alone in this battle. Rapunzel agrees with him, just as Xavier asks her to come join the others in formulating a plan. She promises to be there, but then ventures out on her own, returning to the castle and being secretly followed by Pascal.
Meanwhile, Varian is working hard to perfect his Quirineon formula, but the ensuing result is a powerful explosive. The Separatists decide to use the formula in its current state, as Andrew feels it can be more useful as is.
Using stealth, Rapunzel and Pascal make their way through the castle and manage to avoid several of the Separatists until they reach Cassandra's room, where she is reminded that her best friend is no longer her best friend and finally breaks down over the recent betrayal. But then, she is captured by one of the Separatists and thrown in the dungeon.
As Rapunzel reasons with Varian, he reveals his true feelings and his belief that no one in Corona will forgive him for his past misdeeds, so he wants to make everyone forget about them completely. She tries to persuade him into not carrying out his plan and asks him to be her friend again, but he insists that once the memories of everyone in Corona are erased, they will be friends again. However, Andrew reveals that there has been a change in plans: They plan to use the Quirineon Varian created to destroy Corona instead. Upon discovering the double-cross, Varian tries to take back control of the situation, but throws the wrong chemical and soaks the Separatists in soap. He is subsequently thrown in the cell along with Rapunzel and Pascal.
With Rapunzel and Varian alone together, he tells that her he knows that his father would be ashamed of him. She tells him that she knows how it feels to be betrayed since she was betrayed by Cassandra, and Varian says he thought if he could make her forget everything that happened, they could become friends again and learn to trust again. Suddenly, Eugene and Lance Strongbow arrive, with the former having discovered that Rapunzel had gone off on her own. After being freed, she convinces her rescuers to allow Varian to join them in saving Corona, just as Andrew is sending the King and Queen away from the kingdom, locked in the royal coach, before the Separatists implement their plan.
Rapunzel sends Eugene and Lance to follow the coach while she and Varian concentrate on thwarting Andrew and the Separatists before they can use the Quirineon to destroy Corona. The twosome discover a giant airship, and deduce that the Separatists plan on dropping Quirineon on the city from the air, like bombs. Rapunzel and Varian stow away just as the airship takes off, and Andrew drops the first of the bombs from the deck. However, thanks to Rapunzel's hair, she is able to catch the barrel before it can fall out of reach and explode. Then Rapunzel and Varian get on deck, and she battles the Separatists while he disables the ship and jettisons their enemies. However, they are losing altitude quickly, and if they crash, the Quirineon will explode and destroy the city anyway. Varian has an idea on using the Quirineon to give the disabled airship more altitude so that it will explode out of reach of Corona. He volunteers to do the deed himself, as atonement for his misdeeds, but Rapunzel, knowing that the ensuing explosion will kill him, suddenly jettisons him off the airship and turns the propane on the Quirineon, causing the ship to rise.
Meanwhile, as Kai is driving the royal coach further away from Corona, Lance and Eugene are having trouble unlocking the doors, as Eugene has lost his lock pick in the commotion. Eugene realizes they need the original key to unlock the door, and distracts Kai onto the roof of the coach, while Lance tries to rein in the horse pulling, only to snap the reins loose. Eugene orders Kai to hand over the keys, but Kai refuses. On this, Lance ties Kai up in the severed reins and sends the freed horse running off and dragging Kai behind him, but forgets to grab the key. The runaway coach eventually is sent toward a cliff, but is saved from going over by Maximus and Fidella. However, Kai is not so lucky, as he is pushed off the cliff and never seen again.
Back at the airship, Rapunzel feels she has gotten it high enough to be out of harm's way, and uses the remaining propane to detonate the Quirineon, while using her hair to shield herself and Pascal from the blast. As she falls back to the ground, she uses her hair to swing off a ledge and land safely. Rapunzel and Eugene share a hug in the wake of their toughest victory yet, and she tells him there's still a promise she has to keep.
Inside Varian's home in Old Corona, Rapunzel tells him that she discovered something during her journey and prepares to make one last attempt to free Quirin from the amber where he is imprisoned. She has Varian prepared with a bucket of water and asks him to snap her out of it, in case her attempt does more harm than good. She begins to chant the Reverse Incantation, which slowly melts away the amber, but cannot stop chanting it, and the water Varian splashes her with has no effect. Varian tries to shake Rapunzel awake, only to have his gloves dissolved on contact. Touched that Rapunzel never gave up on him, he declares his refusal to give up on her, and this stirs her awake, causing her to collapse onto her knees. The two hug before Varian cries and embraces his father, overjoyed to know that he is finally free and still alive, and Rapunzel had made it possible, as she promised. Just then, Varian notices the note his father wrote has dissolved along with the melted amber, and he asks his father what was written on it. Quirin simply states that the note said that he was proud of his son, and always has been.
With Corona safe for now, and King Frederic and Queen Arianna still without their memories, Rapunzel becomes acting Queen in their place, and the entire kingdom celebrates a new beginning for itself. In the end, Rapunzel decides to finally open up to Eugene about Cassandra.
- Mandy Moore as Rapunzel
- Zachary Levi as Eugene Fitzherbert, Feldspar
- James Monroe Iglehart as Lance Strongbow
- Eden Espinosa as Cassandra
- Hudson D'Andrea as Little Cassandra
- Jeremy Jordan as Varian
- Clancy Brown as King Frederic
- Julie Bowen as Queen Arianna
- Adewale Akinnuoye-Agbaje as Xavier
- M. C. Gainey as Captain of the Guard
- Jonathan Banks as Quirin
- Bruce Campbell as King Edmund
- Kelly Hu as Adira
- Steve Blum as Attila
- Paul F. Tompkins as Shorty
- Donna Murphy as Mother Gothel
- Dean Winters as Andrew
- Jennifer Veal as Enchanted Girl
- Betsy Sodaro as Clementine
- Khary Payton as Kai
- Richard Kind as Monty
- In this episode, it's revealed that during the events of "Rapunzeltopia", Cassandra discovered inside the House of Yesterday's Tomorrow that Mother Gothel is her biological mother and she was adopted by the Captain of the Guards on the night she kidnapped Rapunzel.
- This is the second time that a fan theory came true regarding a character's family relations, the first being the discovery that Eugene is King Edmund's long-lost son in "Destinies Collide".
- Shorty is revealed to be fluent in miming, able to translate Ulf.
- Rapunzel and the group return to Corona in this episode.
- Varian redeems himself and becomes friends with Rapunzel again.
- Quirin is freed from the amber.
- Maximus and Pascal losing and chasing after Rapunzel's Crown is a reference to the future events of Tangled Ever After when they lost and retrieved Rapunzel and Eugene's wedding rings.
- Starting at the end of the episode, Rapunzel and Eugene wear brand new signature outfits for the third season.
- This is the second time Rapunzel and Eugene wear brand new signature outfits during a new season.
- Rapunzel's reactions to Cassandra's betrayal is applied from the five stages of grief.
- Beginning at the end of this episode, Rapunzel becomes acting Queen of Corona until her parents regain their memories.
- Varian is wearing his gloves at the celebration but his gloves are melted off when he touched Rapunzel while she was chanting the Reverse Incantation.