A scene from the Chinese edition of Mamma Mia, which has had more than 400 shows in the past three years.

Illusion acts designed by professional magicians helped to present how a ghost is trapped between two worlds. When audiences see the actor walking away while his dead body still seen lying on the stage, they were bemused; and they were excited to see the ghost walk through a concrete door, moving things around without laying his hand on it. These magic acts appeared a few times, as powerful tools to engage the audience and "to serve the story", as Ingram, the producer, insisted, "we don't want to make it a show about magic".

The musical theater has seen a growing number of productions adapted from films, Ingram admitted. From Hair Spray to Billy Elliot, and now even 50 Shades of Grey already has a musical production. Ingram himself is working on the adaptation of Back to the Future, a science-fiction movie from the 1990s.

A Broadway production can easily cost $15 million to $20 million to make. The theater adaptation of Spiderman cost $72 million to make, though the musical has not turned out quite well received by the theatergoers.

The film will provide some degree of reassurance for investors to make such a big commitment. Ingram said. Also, the film franchise has established brand awareness among the public, which also helps to build confidence for the live theater box office.

This trend has brought new challenges for theater workers, though. They have to keep coming up with new ideas to meet with the anticipations of today's audiences, who have seen it all, thanks to all the visual effects and computer graphics of the 21st Century: explosion, space walk, superheroes flying between skyscrapers, you name it, they have seen it on the screen, big or small.

Theater provides a different experience though, as Ingram said. Theater has the advantage of building emotional connection with audiences in a strange way. "It has more tools to make people cry, or laugh. This experience of sitting in the dark, with a group of actors, designers and creative people doing a show especially for you, it just can't be copied," he added.

zhangkun@chinadaily.com.cn