Sagan and his wife have written a movie treatment for a feature film called ''Contact,'' about the first contact with extraterrestrial intelligences. ''I'm sworn to secrecy about much of the plot,'' he says. Like a weathercaster he predicts there is a 90 percent probability of the film being made by Columbia Pictures. And he adds that the leading character is a scientist - a woman scientist. At this moment he's writing the novel on which the film will be based and is having a lot of fun with it. ''One of my objectives is to portray in a feature film context the possibility of doing 'Cosmos' type effects on a large screen. That's very appealing to me. It's never been done. And also to get across the idea of scientists as people, not as cardboard cutouts, or malevolent monsters.''
