According to the IMDB, Sky Captain and the World of Tomorrow is set in New York City circa 1939, the film centers on a reporter who notices that the world's scientists are disappearing. Teamed with a skilled pilot and an adventurous colleague, it's up to her to thwart the plans of a mad scientist bent on world domination.
I have found it helpful to do the stretching exercises my physical therapist recommends. Do some core strengthening exercises, such as the ones highlighted at The Mayo Clinic. By keeping your core strong, your back won't put itself in a position to cause that sciatica pain you are having.