The film had test screenings in August 1978 and opened in nine theatres in Texas in early September, grossing $344,785 in its first 10 days. The film went on to become a huge success. Prior to its official release date, the film had grossed $1.7 million, and by the end of the first month of release it had grossed $20 million and went on to gross $76 million at the domestic box office and over $104 million worldwide.
