The trailer for the horror movie "Insidious" uses several techniques to build suspense and intrigue without revealing too much of the plot. It establishes the dark, ominous tone of the film through its logo design and musical score. Quick cuts show glimpses of the disruption to a family's life but raise more questions than answers. The trailer hints that something is haunting the family's son but does not explain what. This lack of resolution, paired with unsettling imagery and sounds, leaves viewers wanting to learn more and see the full story unfold.