Toothless is in love! New trailer, photos from 'How to Train Your Dragon 3'

Bryan Alexander | USA TODAY

Show Caption Hide Caption 'How to Train Your Dragon: Hidden World' trailer Big changes are coming for Hiccup and dragon Toothless in the third and final chapter of 'How to Train Your Dragon.' But, most important, Toothless gets a girlfriend.

Things are getting hot in the dragon world. Toothless the Night Fury has found his soulmate in How to Train Your Dragon: The Hidden World.

The alpha dragon from DreamWorks' animated franchise discovers that he's not the only one of his species left alive in a key reveal from the third and final Dragon film (in theaters March 1, 2019).

He discovers a stunning, fire-blasting female Light Fury.

"She is very rare, very elusive and very wild," says Dean DeBlois, who has written and directed each film since 2010's Oscar-nominated How to Train Your Dragon.

The final film will be a reckoning of sorts for the central duo, the silent Toothless and his human friend, Hiccup (voiced by Jay Baruchel), the cornerstones of an unlikely Utopia where dragons and Vikings, once enemies, exist together in harmony.

On one level, it's the emotionally clumsy Hiccup who has to train his fierce but clueless dragon companion in flirting rituals.

"Toothless is a complete bumbling amateur when it comes to issues of courting," DeBlois says. "He isn't in touch with his primal instincts for these love matters."

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But as his relationship with the Light Fury flourishes, it pulls Toothless away from human influence.

"The Light Fury is an engine of change in our story, representing the call of the wild, which is key to Toothless’ destiny," says DeBlois.

The Hidden World serves as the final coming-of-age installment for Hiccup, who continues his own warrior relationship with the Viking warrior Astrid (America Ferrera). Hiccup has grown from clumsy son of Stoick the Vast (Gerard Butler) to Viking leader following Stoick's death in 2014's Train Your Dragon 2.

Hiccup's new world comes with heavy responsibilities — and the realization that humans and dragons might have different destinies.

But the two species fight a common foe, Grimmel the Grisly (F. Murray Abraham), the big-game hunter who stalked Night Furies into near-extinction. He greedily guns for the one big prize that has eluded him: Toothless.

"Grimmel is effective because he’s so smart, so dedicated to the hunt, so single-minded. He’s the perfect balance to goodness," Abraham says of his evil character. "We like his clarity; he knows exactly who he is."

DeBlois is just as clear and insistent that The Hidden World will mark the last foray for the characters, completing the film trilogy. "I wanted to give this a definitive end," he says.

He was inspired by author Cressida Cowell, who wrote the How to Train Your Dragon children's books upon which the movies are based. Cowell wrapped up the book series with her own explanation for why dragons aren't visible in today's world.

DeBlois will make this point clear in The Hidden World.

"Our narratives are quite different. But we will explain why dragons have disappeared into legend," says DeBlois. "And there are still questions: Could dragons come back? Are dragons still around? All of these will be answered in the third film."