Allie Pennington (Britt Robertson) is used to being the new kid at school, since her parents' jobs as professors of medieval history force them to move a lot. When they tell her she can finish out her high school years at Avalon High, she's ecstatic about being settled for the first time. But a research project for history class turns up some surprising similarities between her new friends and the legend of King Arthur, and she begins to believe that Will (Gregg Sulkin), Jen (Molly Quinn), Lance (Chris Tavarez), and Miles (Joey Pollari) might just be the reincarnated roundtable clan. As the clues fall into place and the moment of enlightenment approaches, Allie is sure she's on the right track, but the real truth is even more surprising than any of them could imagine.