Even though Spielberg "trimmed" the film a few years after its initial release, there still remain some really slow scenes, especially at the home of stars Dreyfuss and Garr.  The actors do there best to work the "family thing" but the scenes are prolonged and drag the story line.  More effective are the ones with Melinda Dillon and the precocious Cary Guffey as a mother and son, respectively, terrorized by nocturnal and unseen visitors.