Assembling a great voice cast is as vital to the success of a LEGO movie as animation and innovation.

The LEGO Ninjago Movie isn’t a spin-off or a sequel – it’s a standalone adventure based on the toy line that also inspired the TV series Ninjago: Masters of Spinjitzu.

The story involves a team of six young ninjas who fight to defend their island home of Ninjago from the evil Lord Garmadon, while resolving a number of issues between each other along the way.

“Every LEGO movie is different,” says producer Dan Lin when STACK catches up with him and the film’s voice cast at Comic-Con. “The first one is an action-adventure, the second was a superhero movie, and this one is our version of a martial arts/giant robot movie.”

Lin, who also served as producer on The LEGO Movie and The LEGO Batman Movie, adds that the challenge is to constantly innovate with each installment while keeping the tone consistent. The LEGO Ninjago Movie will feature some live-action elements to provide a more organic feel. “It’s really different and the most beautiful looking LEGO movie we’ve done so far.”

Ninjago features a stellar line-up including Dave Franco, Justin Theroux, Silicon Valley stars Kumail Nanjiani and Zach Woods, Michael Peña, Olivia Munn and the legendary Jackie Chan.

LEGO Ninjago Movie Action

In voicing the villainous Garmadon, Theroux found the process a liberating experience from an acting perspective. “We’re not in the same room together so you’re left to your own devices with the director and engineer,” he explains. “You can scream and talk and shout for five or six hours and they take it and splice it up and start animating it. I find it incredible – you can improvise with zero consequence.”

“I’ve done this kind of thing before,” adds Peña, who plays Kai, the red Ninja of Fire. “It’s a very passionate thing, but when you see the movie it’s nothing like that. It depends on what take they use, so for all I know [Kai] could be a complete psychopath.”

Perhaps the biggest and most inspired piece of casting was enlisting Jackie Chan, who not only voices the ninjas’ Sensei but also served as the stunt choreographer for the animated action.

“We cast careers – it’s not just voice actors,” says Lin. “Jackie’s strength is not necessarily his verbal acuity or the comedy that comes through in his action. We have a strong script and when the cast come in, every actor brings something new to it. That’s why we have a comedy cast. They record the lines, but it’s their versions and interpretations of the characters. That’s what elevates these LEGO movies.”

We learned a lot about LEGO ninjas at Comic-Con 2017

The LEGO Ninjago Movie is in cinemas on September 21.