A Sidhe Elder incants a spell over a sleeping baby. Twenty years later, a dishevelled looking Princess Elena goes outside to meet her father, Lord Godwyn, and Grunhilda, her nanny. Together, they all set off for Camelot.
Arthur is apprehensive; Elena is not his kind of woman. The Prince's worries deepen further with Uther's declaration: Arthur and Elena are to wed. The guests arrive in Camelot and a celebratory feast is in full swing. Grunhilda sets her sights on Gaius, while Elena is her usual, awkward self and drops soup down her dress.
Elena tells her nanny she doesn't think she is making the right impression. Grunhilda eases her conscience: Who knows what the perfect Princess is, anyway? She reaches into a box, pulls out a frog and hands it to Elena. The Princess pops it in her mouth and chews, clearly finding it delicious.
Uther visits with Arthur and impresses on him how important this union is for the continued security of Camelot. Arthur knows this to be true, but admits he has no feelings for her. The King tells him he'd better find some.
Grunhilda slips out of Camelot and makes her way to the Lake of Avalon, where she summons the Sidhe Elder and reports that all is going as planned. Soon they will have what they want: A Sidhe Queen. Later, Merlin follows Grunhilda to a stream and spies on her. He sees a huge, purple, tongue fly out, snare a fly and then shoot back in at superhuman speed. The young warlock rushes back to tell Gaius what he saw, and they conclude that it must be magic.
Meanwhile, Morgana twists the knife for Gwen, telling her Arthur will have no choice but to marry Elena. Gwen tries to deny her feelings at first, but her emotions are too intense to hide. Morgana maliciously stores this admission for future use.
Gaius, having snooped through Elena's chambers, fills Merlin in. He found the magical dust and tells Merlin that Elena is probably a changeling, inhabited at birth by a Faerie. Merlin knows he has to stop the wedding, but he will need hard evidence, first. The young warlock goes snooping and catches a glimpse of Elena's inner Faerie. He slips off his stool and is nearly caught by Grunhilda, but manages to get away. Grunhilda rushes to the Lake of Avalon to tell the Sidhe Elder that Merlin is on to them.
That night, Merlin is awoken by the Sidhe Elder. A magical battle ensues. A bolt fired from Merlin's staff hits a shelf, which topples on to Gaius' workbench, destroying the potions on it. Merlin regains his composure and, using his staff, disintegrates the Sidhe. Gaius and Merlin survey the damage, quickly realising that the potion they had created to reveal the Faerie has been destroyed.
Gaius carefully prepares another portion for Princess Elena, but they still don't know how to get it to her. Merlin, a mischievous twinkle in his eye, has an idea. Gaius goes to see Grunhilda and invites her to a secret tryst down in the vaults of Camelot. Grunhilda makes her way to the vaults and finds Gaius waiting. As she responds to his pretend advances, Merlin springs from his hiding place and magically seals her inside. Merlin and Gaius then race to Elena's chambers.
Grunhilda escapes and prevents them from reaching Elena. Merlin urges Gaius on and says that he will deal with the nanny. A magical test of wills ensues but, eventually, Merlin is the victor. The young warlock races into Elena's chambers and throws the potion down the Princess's throat. Elena collapses as the Faerie leaves her body. Elena comes to, having never felt so good.
Merlin tells Arthur that he understands what destiny can mean, the feeling of being trapped with no control. The Prince asks what he should do about it and Merlin tells him that an unhappy King does not make for a stronger kingdom. Arthur knows this to be true, but he also knows he is duty bound and does not want to disappoint his father.
The wedding gets underway. As Arthur makes his vow to Elena, he catches Gwen's eye, but she looks away. Elena also has her doubts about this union, but seeing her father and knowing what it means to him, she too makes her vow. They are about to be proclaimed husband and wife, when Arthur interjects. He admits that he does not love Elena and knows that she does not love him, either. They are only doing this out of duty, which is no way to start a new life. Elena agrees, touched by his honesty. The wedding is called off.
As Lord Godwyn and Elena leave Camelot, Arthur steals a moment with Gwen. She jokes that he didn't deserve Elena, anyway. Arthur can't deny it, but hopes he has forsaken her for a woman who is equally as exquisite.
Morgana and Mordred prepare to destroy Camelot (and Morgana plots to destroy Emrys). Is Merlin Camelot€™s last hope?
Merlin star Colin Morgan talks about the important events from episode 511 'The Drawing of the Dark.'
Mordred battles between his duty to his friends and that to his love, but is spared the choice.