for his fourth film about the sensitive subject of anti-racism, he both directed and produced "guess who's coming to dinner" (1967), a groundbreaking story about interracial marriage. it starred spencer tracy, sidney poitier, and katharine hepburn, winning two academy awards with eight nominations. it has been listed in the top 100 films over the last 100 years by the american film institute. however, despite its popularity with the public and its box-office success, many critics gave it negative reviews.