Joseph Gordon-Levitt grew emotional filming The Walk on mocked up World Trade Center

Actor Joseph Gordon-Levitt and his co-stars in new movie The Walk faced an emotional shoot as they prepared to recreate French tightrope walker Philippe Petit's daredevil World Trade Center stunt, because producers had transformed their set into a carbon copy of the New York landmark which was destroyed in 9/11.

The movie focuses on Petit's controversial 1974 high-wire walk between the structure's iconic Twin Towers, but just stepping foot into the fake lobby of the production's World Trade Center brought back a rush of sad memories for the cast and crew.

He explains, "They reconstructed the lobby of the World Trade Center quite thoroughly on this big set, they built it. It was the same as it was (in the original).

"That day, when we were standing there in the lobby of the towers, and it just looked so much like it, I remember just feeling the impact, like, 'Wow, this room doesn't exist anymore but it does (on set). Here it is, we're in it. We're standing in it.'

"I remember in particular, we had two native New Yorkers in our cast - Ben Schwartz and James Badge Dale - and they both on that day, just standing there on that set, they were getting choked up just standing there. I thought that was a really moving, memorable moment."

Despite the rush of emotions some fans may experience watching the drama, Gordon-Levitt, who portrays Petit onscreen, believes the film serves as a "celebration" of the Twin Towers, which had opened just a year before the stuntman's death-defying feat.

He tells People.com, "I think that whenever we think of the World Trade Center towers, all of us are going to think of the tragedy, and it's of course worth remembering the tragedy, but I also think with any tragedy, it's important to remember the positive things, the beautiful memories that you have about whatever it is that you lost.

"That's a lot of what this movie is. It's a positive and warm and beautiful, spectacular celebration of these towers."

The Walk, based on Petit's memoirs, opens in North America at the end of September (15), less than three weeks after the 14th anniversary of the terrorist attacks.

Taking to Twitter.com to mark the tragedy on Friday (11Sep15), Gordon-Levitt writes, "Remembering this morning 14 years ago in NYC, sending wishes for comfort and catharsis to those who lost loved ones."