most science fiction film be big on idea and special effect and but weak on coherence and character development while most horror film be just the same and except without the idea . but david cronenberg the fly take one simple idea and develop it properly and and eschews ( it genuinely terrify ) special effect until it truly horrific climax . and by pay some attention to the personality of it protagonist and it actually make you care about them ( jeff goldblum be excellent in the lead role ) and and add a level of serious reflection on the very nature of human mortality to the raw shock . the mix amount to a gruesomely good film .