Steven Spielberg first decided to make a “Tintin” film 30 years ago, in the wake of his “Raiders of the Lost Ark” success, he told fans at a 30th-anniversary screening of the first “Indiana Jones” film.

The director of “The Adventures of Tintin,” which hits theaters in December, had never heard of the long-running comic book series by Georges Remi, pen name Hergé until 1981, when he saw the word “Tintin” popping up in French newspaper reviews of “Raiders of the Lost Ark.” Intrigued, he had the reviews translated to English, he told the audience during the Q&A portion of the anniversary screening, hosted by Hero Complex’s Geoff Boucher at L.A. Live last week.

“They were basically saying that ‘Raiders of the Lost Ark’ owed a lot to Hergé’s ‘Tintin,’” Spielberg said. “I read the book, and I could see that there was a lot of similarities, a lot of links between both adventure stories, especially the globe-trotting aspect. I thought it was different enough that they could both coexist in the same world at the same time.”

Spielberg and surprise guest Harrison Ford also reflected on the grueling days making “Raiders,” crediting stuntman Vic Armstrong for several key action moments in the film.

“It was arduous, but I was young and dumb, and really enjoyed it,” Ford said. “It was fun to do. Itwas arduous, and it became more arduous as the years went on. I don’t think I ever made it through one of the movies without a major injury.”

Spielberg said Ford’s input was key to developing Indiana Jones’ character as a hero audiences could relate to, in part because he showed vulnerability.

“Harrison approached the whole character with something I wasn’t going to do with the movie, and that was let this hero be afraid,” Spielberg said. “I thought he was going to be a great movie idol, a great movie hero, with many, many iconic possibilities for movie moments. Harrison said, ‘If you want the audience to believe I’m real and not just some guy with a cape, you’d better let me show that I’m afraid. I’ll recover from it OK, but I need to show that fear.’ And Harrison brought that entire tapestry to the entire part, and that transformed the movie for me.”