Visible crew/equipment: When Henry helps pull Mark onto the treehouse at the beginning of the film, if you look very closely to the left you can just make out a crew member dressed in black helping him on to the platform. The crew member then ducks back under the platform.
Visible crew/equipment: In the scene towards the end of the movie where the mother/aunt is holding onto Henry (Macaulay Culkin) and Mark (Elijah Wood), as they are dangling over the cliff, if you look closely at her holding onto Mark's hand, you can see a wire extending from under the sleeve of his coat to his aunt's.
Visible crew/equipment: When Henry pushes Susan off the cliff, look closely at her left side. You can see a wire attached to her hips when she falls.
Answer: Henry caused his younger brother's death by drowning, just like he was planning to kill his sister, Connie.
raywest ★