Brocéliande, where the toadstool was located, is featured in the forest.
While the Storybrooke residents attempt to work on finding a way to free Merlin, Arthur shows up when David comes across an item in a book. They need a special toadstool, the Crimson Crown, that is located in the Forest of Eternal Night (Brocéliande), and David volunteers to go after the item, with Arthur joining him. Before they set out on their quest, Arthur corrects David's assumption that a vacant seat in the Round Table is different from the others, as it belonged to the knight with the purest of hearts, who went on the most sacred of quests, the man he trusted more than a brother until he betrayed him, which he revealed to be Lancelot. David explain to Arthur about why he knows the story of the love triangle that involved the King, Guinevere and Lancelot. When Arthur asks how his friend is, David has to deliver the bad news that Lancelot's dead.
As they reach a bridge that can only be used by one person, David volunteers to take the challenge and snatch the toadstool, but as he attempts to return he is greeted by a fight with phantom knights that ends with David being dragged underwater and Arthur pulling David to the surface and helping him get back to dry land. However, once there, they discover the toadstool is no longer in David's bag. After returning empty-handed, Arthur offers David a seat at the Knights of the Round Table, except that he is offered Lancelot's seat instead of Percival's. However, later that evening, Mary Margaret comes across a very much alive Lancelot, who warns her that the Dark One isn't the only villain in Camelot: Arthur. Lancelot says that Camelot is "not what it seems." And he is right: as Guinevere joins Arthur at the Round Table, he takes out the toadstool that was supposedly lost to add to the reliquary, which holds the magic relics collected by the knights. While it brought him no pleasure to lie to someone he sees as a good and noble man, he must think of his kingdom first.
In the mines, Emma interrupts the Dwarfs' work by taking Happy's pickaxe. This is making the Dwarfs furious that they take their complaints to Mary Margaret and David, who blames himself for not saving Emma. However David is interrupted by Arthur, who tells David that key items from the camp, including a magic bean that would get the displaced Camelot residents home, is missing. David and Arthur stop by the pawnshop first to acquire a item, then begin their search at the Arthurians' camp, where David asks the campers to drink from the Chalice of Vengeance, and points him in the direction of the thief, revealed to be Arthur's squire, Grif, who immediately takes off on horseback, which leads to David and Arthur chasing Grif in David's pickup. David gives Arthur a crash course lesson in driving as David take a piece of wood and gives Grif a lesson in 21st-century jousting, knocking Grif off his horse. Grif later wakes up in the Sheriff's jail and admits that he was tired of how he was being treated, how the Arthurians were all being treated and wanted to hurt the King. However, there was no magic bean found among the stolen items, but at the camp, David recognized the Crimson Crown on the ground and takes it to Regina, who also saw a "?" that she handwritten back in Camelot.
At Emma's basement, Emma takes the pickaxe to Excalibur but breaks it as Rumplestiltskin's manifestation appeared, telling Emma she needs a true hero. Over at Granny's, Hook and Robin look at Zelena's sonogram when Granny hands Hook a meal, which he knew it would come from Emma, who wants to meet him onboard the Jolly Roger for a lunch date together. However, Hook is not impressed, telling Emma that she wasn't the real Emma he knew and loved; however, Emma explains she was doing this to test if he still loved with her, vanishing the moment he says yes. Back at the diner, Hook enlists Robin into a plan to check Emma's house and see what she had in the basement, and as Granny hands Belle a dinner plate, Belle, to her surprise, notices her rose petals being restored, a sign that Mr. Gold is waking up, but when she returns to the pawnshop, he's not there: Emma has taken Gold - and Hook's sword - since they were the last item that Gold touched when he was still alive and before he was the Dark One. Emma wakes Gold up, revealing his heart is a blank slate and promising to make him into a hero, "the purest who's ever lived," she explains, looking over to the Dark One/Excalibur in the stone, "And then I have a job for you."
Unfortunately, at the Storybrooke Sheriff station, it turns out King Arthur is not as honest as he seems; he knew Emma was the Dark One all along and lied about the magic bean. He also has sinister plans to turn Storybrooke into the New Camelot, and has no intentions on returning to their former realm. Its also revealed that Grif was a minion of Arthur, who in order to make sure no one finds out about Arthur's plans, orders the squire to drink a poison of the Agrabahn Viper, and Grif does just that and disappears.
- Ginnifer Goodwin as Mary Margaret Blanchard
- Jennifer Morrison as Emma Swan
- Lana Parrilla as Regina Mills
- Josh Dallas as David Nolan
- Emilie de Ravin as Belle French
- Colin O'Donoghue as Hook
- Jared S. Gilmore as Henry Mills
- Rebecca Mader as Zelena
- Sean Maguire as Robin Hood
- Robert Carlyle as Rumplestiltskin/Mr. Gold
- Lee Arenberg as Leroy
- Beverley Elliott as Granny
- Liam Garrigan as King Arthur
- Sinqua Walls as Lancelot
- Joana Metrass as Queen Guinevere
- Gabe Khouth as Sneezy
- Giacomo Baessato as Grif
- Michael Coleman as Happy
- Faustino Di Bauda as Walter
- David Paul Grove as Doc
- Jeffrey Kasier as Dopey
- Mig Macario as Bashful
- Regina: "Be quiet and listen for once in your life. You've forgot who I am, the Evil Queen. I can be a far greater nightmare than you can possible imagine. But now, my gift to you is a promise. I will make sure your baby is fine, and loved, and safe. Just as I promise, the same will certainly not hold for you."
- Arthur is revealed to be an egomaniac with delusions of grandeur. Rather than assimilate into Storybrooke like the others, he wants to take over and turn it into his new kingdom.