The Harvard School of Public Health, departing from its usual mission of training doctors, said that it would join the television and movie industries in a nationwide program to tell people about the danger of drunken driving. The school will seek to insert anti-alcohol messages into movie scripts, enlist actors as spokesmen, oversee production of television commercials and buy spots in prime time to broadcast them. Dean Harvey Fineberg said it was not a typical role for one of the nation's two dozen public health schools, which train epidemiologists and other health workers. But he said: "I view it as thoroughly consistent with the traditions of the field." Dr. Jay Winsten, head of the school's newly formed Center for Health Communication, said the program's goal is to help make drunken driving socially unacceptable.