The clock and the door
In the beginning of the film, what was the point of removing the minute hand from the clock and loosening the screw on the door hinge?
shareDon't remember if we can tell who is actually making those "atmospheric enhancements" but I remember anything that happens in the first few minutes well enough. I'm usually asleep by ten minutes in. And yes I love the movie.
Any way, it was to increase the creepy and weird atmosphere for the benefit of his guests. Same with the presumed cutting of the phone line "...and I put it to you that this wire has been snip-ped in the last hour..." (or something like that.)
He wanted his guests to get into the proper mood for solving a murder mystery. I think that explains making doors squeak and fake dust on the furniture and fake cobwebs anyway. The clock hand just seems to add a weird touch. Like the "storm only outside when inside" machine.