Tintin is a young, curious reporter whose sidekick is his loyal dog, Snowy.
"The story was easy to tell," Spielberg said. "It was complex, but it was also a story that sort of unfolds like turning the pages of a book and before you know it, it's over."
It was also Spielberg's shortest film.
"I've never made a movie just a little over 90 minutes before - ever," he said. "I'm that 2 1/2-long movie guy that tries to get it down to 2:15 and can't. So this, to me, was a breeze."
Spielberg and producer Peter Jackson used performance capture technology to create this animated world, unraveling a family-friendly mystery along the way.
"This brought me back to my childhood," Spielberg said. "I don't think I ever left my childhood, frankly."
"The audience needs to forget it's animated," he added. "Five minutes into it, if they don't forget that there's a story and there are characters to bond with and there are a lot of laughs and there are a lot of adventure, that needs to erase how we made the movie. If people come out at the end of it and are talking about the stories and the characters, then we've achieved some success."
"The Adventures of Tintin" also features the voices of Daniel Craig and Andy Serkis. It's rated PG and hits theaters on Wednesday, Dec. 21.