Films grow up with their maturing maker. Director John Hughes stays alert to young adults' concerns in the late '80s

FILMS written, directed, and produced by John Hughes are always eagerly awaited - especially by young audiences, who've turned pictures like ``The Breakfast Club'' and ``Ferris Buehler's Day Off'' into major movie events. Mr. Hughes's films are shown in theaters around the world, despite the special problems of translating teen-age slang into a variety of languages. His greatest success outside the United States has come in Japan, where adolescents and young adults are strongly attracted to his youth-oriented stories and characters.

Although his fame is based primarily on teen-age pictures, from ``Sixteen Candles'' to ``Pretty in Pink,'' his work has shown definite signs of growing up in recent months. As he matures, his characters are growing older and a little bit wiser, as well.

His last movie, ``Planes, Trains & Automobiles,'' became a success by substituting two adult comedians (Steve Martin and John Candy) for the teen-agers who normally populate his films. His latest picture, ``She's Having a Baby,'' continues the trend toward maturity. It centers on two characters, played by Elizabeth McGovern and Kevin Bacon, who might have shown up in ``Weird Science'' or ``Some Kind of Wonderful'' awhile back - only now they're out of school, newly married, and making the big decision to start a family.

Making a recent New York visit to launch ``She's Having a Baby,'' filmmaker Hughes assured me that he still keeps young people in mind when he's writing, producing, or directing a movie. He says he'd never make a picture that he wouldn't let his own children see - and they're only eight and 11 years old.

But he acknowledges a new grown-upness in his movies, and says this is a reflection of the time we live in.

``The '80s are coming to a really fast conclusion,'' says Hughes in a sober tone. ``I think the market crash had something to do with it. It's amazing how quickly people have awakened: `Oh, gee! I guess you can't get something for nothing!'

``A lot of these old adages - like, don't tell me, `There's no substitute for hard work' - are true. In the early part of this decade, it was people pursuing sensations. I think now they want substance.''

In the past, Hughes has rarely been accused of overdoing substance in his comedies. But his current position as a major hitmaker is giving him more freedom to follow his own tastes. This includes a preference for avoiding action-packed stories and the violence that often goes with them.

``I'm probably going to stay in comedy,'' says the filmmaker. ``I like it. If I have any medicine to dish out, it's nice to coat it with a little laughter and a little entertainment.

``I like films about interesting characters. I'm not a big plot guy, or a `high concept' person. I like a movie that teaches me something about a particular character I really like. I mean, `The Godfather' for me - when I watch it on tape, I go bzzz past all the murder stuff, and I go for those conversations.''

Hughes likes his movies to be about recognizable people in recognizable, real-life situations. He says his new movie - about love, marriage, and having a baby - is exactly what he's aiming at, because it deals with a crucial period in many people's lives. ``It is important and significant,'' he says of this period, ``not because of what happens, but what doesn't happen. It's that settling-down period. After you're done with school and you're married or with someone - or not, it doesn't really matter - it's Saturday night, and you can't pick up the phone and call all your friends. You have to go to work on Monday morning. You're responsible for a lot of things. And life is getting quiet.

``Now what? What do you do now? It becomes much more difficult, because the decisions that you make are enormous. Am I gonna get married? Am I going to bind my life to this person?''

Hughes expects his characters will keep growing and evolving in future films. Right now, for instance, he's thinking a lot about how fathers deal with their families. And there's every chance that ``the dad situation,'' as he calls it, will appear in his movies before long.