Paramount kicked off the big studio presentations at San Diego Comic-Con in high-style, showing off the cast and scenes from its upcoming animated feature, Transformers One.

The studio has been hyping up the feature for a couple of months. It showed a work-in-progress version at the Annecy International Animation Film Festival in June, while a fan screening hit Los Angeles earlier this week – so the panel was light on news.

It did, however, more than make up for that with the charm of its crowd-pleasing voice cast: Chris Hemsworth as Orion Pax, who will evolve into Optimus Prime; Brian Tyree Henry as D-16, who will turn into villainous Megatron; and Keegan-Michael Key, whose B-127 will become Bumblebee.

The trio were on stage with director Josh Cooley and longtime Transformers franchise producer Lorenzo di Bonaventura.

Key had the crowd laughing by making Transformers sound effects and singing the classic theme song. And later, during the Q&A, a female guest directed her question to Key and Henry, throwing a casual “And Chris, I guess,” which generated much ribbing of the Australian superstar and became a running joke.

“Oh this is historic!” howled Key.

And even after the last question was posed, moderator Anthony Breznican called on one more audience member, a little boy. When told he could ask one question, the boy said “I have seven.”

Also helping win over the audience, which was already in a very receptive mood, were poster giveaways and a raffle to win a shiny electronic Matrix of Leadership prop that was autographed by the cast.

Earlier, the actors noted how they played with the toys as children and shared their connections to the franchise.

“The nostalgia around it is something I hold dear to my heart,” said Hemworth. “The stories represented justice, injustice, right and wrong, the subtle lessons.”

Henry noted that his parents always seemed to get him villain characters, Transformers or otherwise. “I would always make them the hero,” he said of the toy characters. “Villains don’t always start (as villains). Something happens when they follow their righteousness to its final place. So being able to actually be Megatron is a lifelong dream come true.”

That is fitting as the movie acts as an origin story to how Optimus Prime and Megatron become archenemies, with the movie, set three billion years before the stories audiences know, showing how the two best buds slowly grew apart.

It was the first time that Hemsorth has worked in animation, and he said it required a bit of trust in process.

“The way animation works is different from a film set where you’re interacting, and doing things in the moment,” he said. “We would individually shoot our scenes. Luckily, we would see what each other had done and that would influence my performance … You sort of hand it off and hope it gets to the right place.”

Henry, meanwhile, said the movie’s story about the loss of a friendships would be relatable to broad audiences. Calling it one of the worst heartbreaks, he noted, “The loss of a friend is something all of us can understand.”

Speaking of friendly, Hemsworth stuck around briefly after the panel, shaking hands and signing autographs to the dozens that swarmed the stage area hoping for a close-up look at the star.