In the beginning, the first shot through the window of Howard Wilton installing the screen shows a list of chores in the foreground with seven items on it, beginning with "Sweep porch", "Water flowers", etc. Six of the items have been checked off, with only "Clean sink" being left. In the closeup of Howard that follows, the list has changed; it now has a title ("Things To Do") and has only four items, "rake yard", "clean windows", "Rubbish", and "Screens".
When the delivery boy is unpacking groceries, Wilton pulls down the shade over the window in the door. When he lets the kid out, the shade is up again.
When Howard and Helen are fighting in her bedroom, he grabs her shoulders several times, but doesn't tear her clothes at all. When she faints and he leaves the room, there are no tears to any part of her blouse; yet when she wakes up later on, her left shoulder is bare due to a huge rip there.
Much is made of how the dog barks wildly every time it sees Howard; however, at the end when Howard is at the door, the dog runs by without even paying attention to him.
This likely is due to the dog having been away from the house for so long and wanting to get back to Helen. Also, it is believed by some that pets can sense a person's character. As Howard, at that time, was in a congenial state and leaving (quite contrary to his earlier agitated state), it's possible the dog sensed he was no longer a threat to Helen.
This likely is due to the dog having been away from the house for so long and wanting to get back to Helen. Also, it is believed by some that pets can sense a person's character. As Howard, at that time, was in a congenial state and leaving (quite contrary to his earlier agitated state), it's possible the dog sensed he was no longer a threat to Helen.
(at around 3 mins) When the murder victim, Mrs. Warren, is revealed, she blinks.
(At around 1 min 50 sec) As Ryan's character cleans the window, a calendar for December 1918 is visible, showing Christmas on a Thursday. In 1918, Christmas actually fell on a Wednesday.
When Helen backs away from Howard after he discovers the secret message on the check, the shadow of a crew member is cast all over Helen's back, and is seen holding his hand to his head, then putting it down.
When Howard Wilton leans against the front door after having been laughed at by Ruth, the large shadow of the microphone is visible on the door and slowly gets out of the shot.
When Helen is locked in the basement and calls to Jimmy through the window for help, he hesitates ,momentarily,. to see where the call is coming from, but then runs off to the ice cream man. Helen does not call him again when he's still in earshot, but only calls him again as he's running off, too far away to hear her..