We’re back aboard the Jolly Roger on tonight’s Once Upon a Time season 4, episode 16.

Ariel’s story may have taken a few pages out of the Hans Christian Anderson and Disney playbook, but Ursula’s back story is nearly a play by play of the 1989 animated classic. However, instead of having a sea witch grant her passage to a new world, she has a suave pirate with a talent for pulling off lather and eyeliner.

Once Upon a Time season 4, episode 16 takes us under the sea to give viewers some insight to how Ursula’s happy ending disappeared. As Hook and his crew nearly sail into rocky coves following the sirens’ call, something breaks their allure and they save their ship. Hidden in the depths, a stubborn Ursula stands up to her father Poseidon. Her voice is the only gift that remains after her mother’s brush with the humans went awry years ago. But as long as she lives under his ocean, she must play by his rules.

Back in Storybrooke on dry land, August’s happy return to a boy is over as the harsh reality of being an adult hits him harder than most. Before the curse hit, August met a man who was also looking for the Author, but died before he could get all the information. Regina takes her only free moment to conjure up a smoke monster to get a message to the hero brigade. No one bats an eye when the purple cloud takes over Mary Margaret to deliver the news of Gold’s presence.

Belle is less than thrilled to hear that Rumple not only came back to Storybrooke, but that he found yet another way to deceive her. With the dagger gone, the stakes are raised and Killian takes matters into his own hands. In order to speed up the investigation, he decides to offer Ursula a chance at her happy ending since he was the one who took it from her.

In the past, Ursula uses her cunning ways to slip into a bracelet from Poseidon’s vault to sing a familiar tune on those shores up above. Hook’s infatuation with her story about taking her mother’s voice away from causing pain, inspires him to take her away from her troubles. But since Poseidon is the ruler of the seas, he corners Hook into accepting a trade — his daughter’s voice for a vile of squid ink that would remove the magic of even the Dark One.

Poseidon hands over a seashell to capture the voice and leaves Hook to prove once and for all how terrible humans can really be.

Convincing Ursula that he still holds the one thing that she desires most, Hook entices her to take a dip in the water and lure his ship back from the Enchanted world. But what comes back is less than ideal. After Blackbeard took the trade, he began terrorizing lands. That is until he reached Arendelle where Elsa used her more finely tuned ice magic to shrink his ship.

With some help from Will, Hook acquires a potion to bring his ship up to pirate standard size. On board he find Ursula’s voice locked away, but it does not come out willingly. A failure in her eyes, she refuses to divulge any information to Hook. Old habits die hard as Hook slips back into his vengeful ways, pulling a gun on the sea witch and getting thrown into the sea as a result. Luckily Ariel was captured aboard the ship when it was enchanted and brings Hook back to shore.

But how did Hook come about her voice in the first place? After divulging her father’s plan to trap her voice, Ursula takes Hook’s admittance as a sign of trust and gets him the ink from her father’s vault. Win-win, right? Not when you mess with the ruler of the seas. Poseidon, destroys the ink and Hook, in turn, destroys Ursula’s happiness by taking her voice and holding it hostage.

August is not talking as openly or as quickly as Gold desires so he borrows a little something from the fairies to get things moving. Reminding him what makes the real boy not so real, Gold sends August back his wooden state. When he comes back to being a grown man with scruff instead of wood shavings, Gold brings out another component of Pinocchio’s tale. As he tells them lies, his nose begins to grow. Soon, Gold, Regina, and Maleficent are off to the Sorcerer’s house in search of the door.

Back in the past there is one final piece of Ursula’s puzzle to fill in. After she returns voiceless to her father, she refuses to take anymore of his guardianship and power. Taking his trident she fixes her form to match the sea witch she was named after. (That solves that mystery, only four episodes later.)

In the present, Hook sends Ariel to retrieve Poseidon for a happy ending. Since he enchanted the shell, only her father could give her singing voice back to her. Voice restored, Ursula realizes she misses more than just singing, she misses her life with the hot crustacean band. One villain down.

As rough as it was to get Ursula back to her happy ending, Hook does not feel the relief of a job well done. Instead he focuses on not only how easy it was to slip back into his old ways, but also what it means for his own happy ending. There are still many signs of a villain lingering within him putting his happy ending in the hands of the Author rather than a bunch of people who believe in the goodness that exists at his core.

And his theory is not crazy. Before Ursula heads back, she holds up her end of the bargain. As long as the Savior exists, the Author cannot give villains their happy endings. But Gold has a plan far worse than removing Emma from the picture entirely, he plans to fill her heart with darkness.

Hook isn’t the only one having second thoughts about the goodness that exists within. Regina nods off and dreams that Robin returns to her. But a rude interruption by her Enchanted Forest regal self interrupts her happy ending.

August’s rescue mission arrives and Mary Margaret takes her out Tangled skills and knocks her out with a pan. August reveals that although he said the door was in Storybrooke, he did not lie when he said he didn’t know where it was. The door, it turns out, is the illustration. The Author is trapped in the book.

Watch Once Upon a Time season 4, episode 17, “Best Laid Plans,” next Sunday, March 29 at 8:00 p.m. ET on ABC.