Values Dissonance: Criminals being described as "Jews"/"Asiatic" with the clear indication they're mean to be uncivilized is hard to read today.
The 1934 film:
Awesome Music: Arthur Benjamin composed the first important score for a Hitchcock movie, centered on the Storm Clouds Cantata, the piece performed in the climax, which he wrote from scratch as a full-length composition. Many viewers no doubt assumed it was an actual pre-existing Classical Music piece. Bernard Herrmann liked it enough to re-use it for the remake.
Ending Fatigue: The police shootout. The assassination has already been thwarted, and even Betty still being in danger can't add much to the excitement of a bunch of faceless nobody cops trading shots with the bad guys for ten whole minutes.
Nurse Agnes is a notable oddball villain. Picture Nurse Ratched as The Dragon, with hypnosis skills to boot.
Growing the Beard: This is usually considered Alfred Hitchcock's first real "Hitchcock" film, with its blend of suspense, inventiveness and humor.
Harsher in Hindsight: Ramon falling to his death after getting shot by Jill. Frank Vosper, who played Ramon, died three years later after falling off the deck of an ocean liner (officially ruled an accident, but rumored to be a suicide).
Adaptation Displacement: People who aren't Hitchcock buffs are often surprised to learn that it's a remake.
And You Thought It Would Fail: "Qué Será, Será" again, big time. Doris Day initially was extremely reluctant to even record the song, calling it "forgettable children's song". It went on to win Oscar for the Best Original Song, ran second on US Billboard chart and first on UK Singles Chart and, ironically, ended up as a theme song for Doris' own The Doris Day Show. It is now #48 on American Film Institute's 100 Songs list.
Narm: "How are you going to get the child out of here? EH!? EH!? EH!?"
Nightmare Fuel: The scene near the end, after the Ambassador has made it clear to the Draytons what must be done to Hankto prevent him from implicating them; though nothing is spelled out, the way that one of Mr. Drayton's minions starts sinisterly wrapping a piece of rope around his hands as Drayton gives them his last orders says everything. Both Hank and Mrs. Drayton being clearly afraid and listening to the nearing footsteps - believing that it's Mr. Drayton who's coming - only heightens the terror.
Remade and Improved: This version is widely considered better and is more well-known than the original 1934 version. Alfred Hitchcockdirected both versions and while he still liked the original, he acknowledged that the remake was technically superior in some ways, stating "Let's say the first version is the work of a talented amateur and the second was made by a professional." While the original isn't considered a bad film in the slightest, the remake is generally seen as more polished, such as having a more consistent tone, a tighter narrative, more character development, and better pacing; a recurring criticism of the original is that the pacing feels too frantic in some places and too slow in others, with many finding that the climactic shoot-out in particular wears out its welcome (Hitchcock notably omitted it from the remake).
She Really Can Act: Viewers who only know Doris Day from old-fashioned pop music and romantic comedies might feel pleasantly surprised by her dramatic potential in this movie, especially after her character receives word of Hank's kidnapping.
The scene in the 1956 film where Jo learns about her son's kidnapping is wrenching. As listed above, Doris Day does an excellent job of acting the character's fear for her son's safety, her anger that her husband sedated her, and her confusion brought along by the pills.
