Belgian writer-director Lucas Belvaux's clever and engrossing trio of parallel films, collectively known by the hushed title The Trilogy, is as much a feat of diagramming as it is of drama. The three different stories, to be released sequentially over the next couple of weeks, are presented in three different styles -- thriller, romantic comedy, and melodrama -- but the plots unspool simultaneously. The main characters in one appear as minor characters in the others. Each film stands satisfyingly on its own as a genre piece, but the triplex provides added understanding of character and consequence. Some people solve crossword puzzles to achieve elegant down-and-across satisfaction like this.
''On the Run,'' the first film, sets the machinery up on a taut noir note. Belvaux himself plays Bruno, a far-left revolutionary escaped from prison and trying to evade capture; shadows are as crucial as light. The second, ''An Amazing Couple,'' about a hypochondriac and his schoolteacher wife (Ornella Muti) who thinks he's carrying on an affair, luxuriates in fluidity and color. ''After the Life,'' the third, pulls in tight on a cop and his drug-addicted wife. Genre-hoppers like Steven Soderbergh ought to love this neat triple doozy.