What is the name of the BeeGee's song in the movie Staying Alive ...?

the scene where John Travolta and Finola Hughes are on that first date...they get a carraige in the park, etc....ive been trying to figure it out for like 20yrs, its driving me crazy, i want to dwnload it but do not know the name, it is not on the soundtrack...HELP me pls music lovers!!!