The opening sequence of the film Triangle establishes the mysterious and psychological tone. It begins with a woman crying over her son who had a bad dream, expressing fear and unease. The sequence then shows images of a peaceful suburban neighborhood, but with unsettling musical cues and the woman seeming confused. It climaxes with her finding a toy boat knocked over in a pool, symbolizing a coming yacht accident and creating a sense of foreboding, before she walks away with the toy in hand.