So poorly done it lends a clunker like "Ghost" the illusion of depth, "Heaven's a Drag" boasts bad dialogue, a cliched story, unimaginative camera work and negligible acting. The script deserves particular bile, being at best an embroidery of platitudes and at worst a mockery of individuals in real pain. The plot follows the relationship of Mark and Simon, a gay couple in London. Mark has HIV and Simon doesn't, so they have an "open" relationship that allows Simon romantic interludes while Mark stays home to watch an AIDS quilt documentary over and over again. Mark dies; Simon lives. Mark returns as a ghost and becomes a pest. It's an allegory about letting a loved one go. There is weeping. "Heaven's a Drag" (formerly titled "To Die For") takes an important subject the effect of AIDS on gay couples but, amazingly, treats it with light purpose. Those sufficiently iron-willed and stout-stomached to stay to the end will be rewarded with the mother of all ridiculous denouements. It involves blinding light and angels with their butts showing. The real tragedy, though, is that the shallow conception of the well-intentioned filmmakers ends up ridiculing the very people to whom they dedicate "Heaven's a Drag": "the brave who still live in hope." One can only think the brave deserve something better. Starring Thomas Arklie and Ian Williams. Directed by Peter Mackenzie Litten. Written by Johnny Byrne. Pro- duced by Gary Fitzpatrick. A First Run release. Comedy/drama. Unrated. Running time: 96 min.