Director Destin Daniel Cretton didn't want 'Shang-Chi and the Legend of the Ten Rings' to feature a "broody, quiet" hero.

The 42-year-old filmmaker admitted part of the appeal in casting Simu Liu as Shang-Chi was his "charisma" and ability to handle comedy because he was determined to "surprise" audiences by making the Master of Kung Fu charming and funny.

He said: "The voice of Shang-Chi was definitely something in that vein, which is what we were looking for. We didn't want a broody, quiet Asian character. We wanted a character who looks like me or Simu to surprise people with charisma and with a more outgoing personality, which we just don't see very much of, particularly in this genre.

"So, that was something that we were looking for and Simu really fit that box."

The director recalled how "cool" Simu looked when he donned his character's full costume for the first time.

Asked if he remembered the first time the actor wore the outfit, he told 'Entertainment Tonight': "Yeah, it was really cool.

"It was in Sydney and he did the first screen-- I mean, the very first, first time you see it, it's actually not that cool, because it's not the full suit. It's like a cloth version of the suit and it looks like a really bad Halloween costume, like, because it's not fitted.

"But once he put on the first version of the fitted, real suit, it was very exciting."

Simu famously used Twitter to campaign for the role, but it seems his pleas were unnecessary because Destin didn't know about the social media posts until after he'd cast the actor.

Discussing the casting process, he said: "I honestly didn't know about the tweets until, I don't know, when it first started coming out in headlines, which was well after he was cast.

"I mean, our version of the story -- the reality -- is maybe a bit less fairy-tale like, and a little more practical. We did a very big search and we saw a lot of really great actors for this role. And Simu was the best.

"He just really connected to the character in a very special way and was able to show both strength and vulnerability and the natural charisma that we wanted for a character that would be very relatable to people."