Back at the lake, Odette and the other swans are inconsolable. The spell cast upon them can’t be broken now that Prince Siegfried has pledged his eternal love to the wrong beast at the Betrothal Ball.
Prince Siegfried finds the swans on the shore comforting one another. He runs to Odette and explains that von Rothbart tricked him, thus it probably wasn’t his fault that he pledged eternal love to the wrong swan. Odette honks, “Okay, honest mistake,” because everyone in this ballet has the attention span of a fruit fly and really wants to get married/not be a bird anymore. So, Siegfried is forgiven. Though Odette does gently remind him that she’ll be a swan forever because of his huge-ass mistake.
Von Rothbart and Odile show up, and von Rothbart tells Siegfried that he must marry Odile because he stamped it red hot, black magic, no erasies. As you might expect when two dudes face off in the presence of girls/water fowl, a fight breaks out. A ballet fight! Which is basically a lot of kicking, fake jabbing and the occasional pirouette.
Post-fight – and because nothing ever really gets sorted with wrestling – Prince Siegfried tells von Rothbart that he would rather drop dead than marry Odile.
Odette laments that death is the only way for her to be freed from von Rothbart’s spell, and truth be told, she’d rather croak than live without Siegfried. So, à la Thelma and Louise, Siegfried and Odette jump into the lake and die.
Their sacrifice destroys von Rothbart’s powers and frees the other girl-swans from his spell. And then? Those gals beat the shit out of von Rothbart, driving him and Odile into the water where they meet with a glug-glug death.
Oh, and then spirits of Prince Siegfried and Odette ascend into the heavens above Swan Lake. So… happy ending.