WARNING: The following contains major spoilers for Legacies Season 3, Episode 1, "We’re Not Worthy," which aired Thursday on The CW.

Season 2 was rough on the supernatural students at the Salvatore School for the Young and Gifted. And while Hope and Landon remain asleep, at least Josie’s trying to get back to normal after Hope helped her end her black magic binge in the second season finale. Realizing his charges have gone through a lot, in the Season 3 premiere, "We're Not Worthy," Alaric decides it’s time to let the kids be kids, so he and MG plan a field day for the upper school. Of course, like anything at the Salvatore School, things don’t go quite like they’re supposed to, and this time, the Super Squad encounter a figure straight out of the legend of King Arthur.

The beginning of the episode makes it clear that while the nice version of Josie is back, the rest of the school isn’t ready to forgive her, especially Alyssa, who Josie killed when she was under the influence of black magic. Lizzie, determined to defend her sister, goes back to her mean girl ways in a bid to help out. She takes control of the witches from Alyssa and tries to get Josie back in their good graces by ensuring they win at tug of war. But Josie put her magic away at the end of Season 2, so Lizzie’s magic-dependent plan for victory instead ends in the witches’ loss and Josie in a mud pit, followed by Josie begging Lizzie to let her take her knocks on her own.

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Meanwhile, as Chad mocks the absent Necromancer in his lair, a being unexpectedly rises out of Malivore’s pit and introduces herself as Nimue, the Lady of the Lake. Yes, that Lady of the Lake. While recent Netflix series Cursed and Wizards: Tales of Arcadia have included this character from the legend of King Arthur, it’s somewhat surprising to see her appear on Legacies -- especially since her emergence from Malivore’s pit means that, in the world of the show, her participation in King Arthur’s story has been forgotten for who knows how long. Still, Nimue’s on a mission and it has everything to do with King Arthur’s sword, which the characters do know about, so apparently parts of the legend has survived.

In fact, unbeknowst to the Salvatore School students, Wade was playing with the magical sword Nimue’s seeking earlier in the episode. So following the tug of war debacle, Wade stops the field day fun to present Nimue and ask them to weigh in on whether they should let her have Excaliber.

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While Nimue is desperate to convince the kids to give her the sword so she can protect it against an evil power coming for it, the students have been confronted with similar dire circumstances so many times, they don’t take her all that seriously -- until the Green Knight, the armored monster she warned against, shows up. The Green Knight's arrival leads the sword to fall into a stone and Nimue explains the only way to retrieve it and save the day is for someone worthy to pull it out.

While the rest of the school flees, the Super Squad stays behind to take on the Green Knight who, due to a curse placed on his by Nimue, is moving verrry slowly but relentlessly toward Excaliber. After Josie, Lizzie and the others attempt to remove the sword from the stone and fail, the gang tries to determine who would truly be worthy of wielding it and conclude Hope has all the qualities needed. But it turns out Nimue should had been more specific earlier because what she meant by worthy has nothing to do with noble qualities. Instead, she's talking about family lineage: to be worthy of retrieving the sword, the individual has to be related to King Arthur.

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As far as the Super Squad knows none of them are related to the king, so they organize to make a last stand against the Green Knight, however futile it may be. Just as things are looking hopeless, Rafael shows up and, to his and everyone else's surprise, removes Excalibur from the stone, allowing him to easily defeat the Green Knight. After the danger is gone, Rafael tries to give Nimue the sword, but she informs him that, as a descendant of King Arthur’s, it’s rightfully his. Before dissolving into water, she tells him if he does better with Excalibur than his ancestors, she won’t return.

It’s hard to know what this revelation about Rafael means for him and the rest of the Super Squad. It’s possible Rafael’s magical new sword will become an important weapon during the season, but perhaps even more interesting is the opportunities it may open up for foster kid Rafael to learn more about his family tree, a quest he started when he met his birth father last season. Knowing he traces his lineage all the way back to King Arthur could open up all sorts of interesting possibilities for Rafael this season.

Legacies stars Danielle Rose Russell, Jenny Boyd, Kaylee Bryant, Quincy Fouse, Aria Shahghasemi, Peyton Alex Smith, Matt Davis, Chris Lee, Ben Levin and Leo Howard. New episodes air Thursdays at 9 p.m. ET/PT on The CW.

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