Two 'Transformers' sequels in pipeline
Director Michael Bay has also told how his version of the 1980s cartoon classic is heavy on the special effects and has cost some £50 million.
A trailer of the movie, to be released next month after several delays, is said to demonstrate impressive CGI as the Autobots go head-to-head in battle with the Decepticons.
Bay said he thought the combination of human actors and heavy effects had paid off. "It's got a lot of action, but at the same time it's very funny and it's got heart," he explained. "I only wanted to do Transformers if I could do it realistically."
Meanwhile, the DreamWorks studio has given the provisional go-ahead for two more movies.