Joseph Gordon-Levitt was surprised by how humble Robert Zemeckis is.

The actor teamed up with the legendary filmmaker for new movie 'The Wire' and even though Robert has directed films including 'Forrest Gump', 'Cast Away' and 'Back To The Future', he wasn't afraid to admit he didn't have all of the answers.

Joseph told Collider: ''The thing that stood out about Robert is his humility, which is incredible considering all he has done in his life and career.

''One of the things he would always say is when blocking out a scene is 'here's what I know' and then 'here's what I don't know' and just to have a guy that's as great as he is saying, 'here's what I don't know', that takes so much confidence and humility and brings out the best in everybody.

''When the person in charge is humble enough to ask for help and bring everybody in to the process, it inspires everyone to do their best.''

Joseph stars as Philippe Petit in 'The Walk', which is about the Frenchman's jaw-dropping effort to cross between New York's twin towers in 1974, and Joseph has claimed the death-defying stunt had a special meaning.

He said: ''It's beautiful and physically daring but there's a metaphor, too.

''It takes courage to do anything. It's so easy and cowardly to say 'I don't care' or 'I can't be the person I want to be.'''