Hex returns for the Grimoire of Archamada which contains a spell that will make him more powerful than ever!
The episode starts off with Ben and Gwen standing at a castle, and Ben questions Gwen if she’s sure it’s haunted. Gwen explains that Castle Kleinhart was once known as “Witches End” because anyone accused of witchcraft who entered never left. Ben questions why there’s a bunch of people behind them wearing cloaks, and Gwen states she has no idea (while she puts her cloak on). He’s also confused as to why the poster says I.J. Crowling on it. Ben transforms into XLR8 and runs into the Castle. He looks around the castle using the brochure. The announcer over the PA calls everyone up to the auditorium. XLR8 runs to the auditorium, and is soon run over by a large number of fans. Crowling steps out and greets her fans. XLR8 looks over and sees a familiar shadow, that he believes to be Hex. However, he runs over there and finds out it’s nothing. Crowling explains the origin of her Grimoire series, and begins to read it. As she continues to read it, XLR8 is gets more bored by the minute. He then runs away. Hex teleports in, and interrupts, claiming that Crowling has no idea of the power that she has in her hands. He stills the book, and casts an incantation that fires a beam into the sky. XRL8, from somewhere else in the building, spots the beam in the sky, and runs to investigate.
Meanwhile, the power of Xus continues to flow through Hex, and change him. He transforms into a giant serpent, and calls himself Hexxus. Gwen begins throwing books at Hex, however she is easily beaten by him. XLR8 soon arrives and throws more books as him. He runs over to Gwen and Crowling to assist them. Hex quickly recovers however, and XLR8 runs to distract them while they break free. XLR8 hits him and breaks one of his teeth with a statue. He prepares to do it again, however, his watch times out. Then, Hex throws him across the room. Gwen tries to tell Ben that he needs to grab the book in order to beat him, however Ben ignores it, and continues to run away. Ben is eventually cornered by Hex. He attempts to stall for time, but ultimately fails. Hex pushes him off of a balcony, and Ben transforms into Diamondhead to save himself. He manages to get the upper hand on Hex. Gwen runs up to Diamondhead, asking him if he got the book. Ben however still misses the point of retrieving it. Tired of all this, Hex uses a spell that makes him grow even larger. Ben then realises the source of his power. Diamondhead manages to separate Hex from the book. He then punches Hex in the face as he times out. Right as Hex tries to attack Ben, Gwen picks up the book and casts a spell that turns him into a mouse. Hex immediately transforms back into a human, as he makes his escape, promising that their battle isn’t over. As Gwen runs to get a copy of one of Crowling’s books, Ben asks if she can sign a book “for a friend”.