Everyone knows the story--brilliant scientist creates amazing invention (teleporter!) and, in testing it, merges himself with a fly that, unbeknown to him, zips about his second telepod. What follows that mishap could best be described as degeneration, as Seth Brundle, the scientist, becomes Brundlefly.
Obviously, though, the movie was made by David Cronenberg, master of venereal or bio- horror. He loves exploring the body and the many ways it disintegrates or morphs; he loves making audiences squeamish with glistening viscera that serve a higher, more philosophical purpose. If Rabid was about STDs, then the Fly is about love in the face of decay. Reading into the story too much would be reductive--The Fly isn't about watching Brundle die from any particular disease; it's about watching Veronica helplessly stand witness to her lover's slow, unalterable demise. It might also be leftfield, allegorical support for euthanasia, but I'm more inclined to believe that the ending resulted from the necessity of a tidy narrative than it did from Cronenberg's desire to include an encrypted message.
But is it any good? Yes, it is. The Fly works on the level of symbolism, but it's also an enjoyable and frightening horror film. It's got the gore and the scares, but it's also intelligent. The Fly is a brilliant commercial horror movie inasmuch as it manages to stay true to the director's vision, while also delivering what audiences expect from a scary movie. It's also wonderfully shot and acted (Jeff Goldblum already looked like an insect; Cronenberg got him to act like one as well).
With The Fly Cronenberg also achieved something few directors could--he made a remake better than the original. The Fly from the 1950s was fine, but it wasn't really that frightening; it's actually a little silly. Cronenberg rewrote the script and turned the earlier film on its ear. This Fly is scary, smart, and, unlike most of Cronenberg's films, lacking in gallows humor; it's actually among his more serious endeavors.
The Fly is a fantastic piece of film-making that should appeal to those in the mood for a taut horror flick or an intelligent, though coded, exploration of an interesting idea.