Note that there are POTENTIAL SPOILERS in what follows, although some of this may not make much sense if you have not seen the movie recently. Please add your comments if you have any opinions about this analysis.
After watching the Manchurian Candidate recently I was struck by the scene where Janet Leigh and Frank Sinatra meet on a train and exchange a series of bizarre lines. Through the entire scene, I was uncertain whether they were a) having a real conversation, b) were exchanging a series of code words, or c) Leigh was a Communist dropping post-hypnotic suggestions to Sinatra.
I was pleased to find that Roger Ebert had his own suspicions, writing in his Great Movies review of the film:
Is Sinatra's Maj. Marco another Manchurian sleeper, and is Rosie his controller? If you look at their scenes carefully, you find that she broke off her engagement immediately after their awkward train meeting and before their first date. Reflect on the scene where she talks about Marco beating up "a very large Korean gentlemen," and ask yourself what she means when she calls this man, who she has never seen, "the general." I don't know. Maybe Rosie just talks funny. It would be a nice touch, though, for this screwball story to have another layer circling beneath
In fact, I believe that their relationship suggests that there is something going on beneath the surface--either Leigh is a spy or she is attempting to drop post-hypnotic suggestions to a brainwashed Sinatra. Consider the first few lines of dialogue in their first meeting:
Leigh: Maryland's a beautiful state.
Sinatra: This is Delaware.
Leigh: I know. I was one of the original Chinese workmen who laid the track on this stretch. But nonetheless, Maryland is a beautiful state. So is Ohio, for that matter.
This sounds precisely like an exchange of code words between spies--or a post-hypnotic suggestion. Sinatra continues:
Sinatra: I guess so. Columbus is a tremendous football town. You in the railroad business?
Leigh: Not anymore. However, if you will permit me to point out, when you ask that question you really should say, 'Are you in the railroad line?'
Again, this is even more suggestive, as though Sinatra got the code wrong and Leigh is correcting him, or that his response to the questions is a part of the post-hypnotic suggestion and she is trying to keep him on track. Each character also asks the other--for no apparent--reason whether they are Arabic. At the end, Leigh tells Sinatra her address--Apartment 3B--then repeats her phone number twice, forcefully, as though assuring it gets marked in his hypnotically suggestive mind.
The scene is immediately followed by the entry of Chunjin--the "large Korean man"--into Raymond Shaw's office looking for work. After this scene is a brief interlude with Mr. and Mr. Iselin, then we see Sinatra walking inside an apartment building. Over his shoulder we see a door which is clearly marked "B" in 3 distinct shots--3B?--though we never see the marking of the door he is knocking on. Is this the room Leigh was suggesting he go to? Chunjin opens the door--it is actually Shaw's apartment--and Sintara assaults him.
We next see Sinatra in the police station. Leigh arrives after having been called by the police--Sinatra remembered her phone number! And she shows up! They get in a taxi and she mentions her apartment--"Apartment 3B" he says. On the one hand, he remembered the room number. On other hand, it seems like it is probably her real apartment number and that she did NOT send him to Shaw's, where he was already headed. She then makes a comment about "the general"--she is actually, jokingly referring to General George Washington, whom she admittedly confused with Washington, D.C., so this is a red herring. It is also here that Leigh mentions ditching her fiancee after having met Sinatra once for five minutes.
Shortly afterward we see Shaw's snake bite accident, where he is miraculously discovered and treated by the flirty Jocelyn Jordan (Leslie Parrish) another attractive blonde who even more miraculously has a razor but no spare cloth and so proceeds to remove her blouse to treat his wound. Is this all a coincidence or was she planning to seduce him? After having seen Leigh's strange behavior, this meeting seems almost too good to be true as well. Immediately afterward, Shaw asks Jordan's father for her hand in marriage!
Finally, note that Parrish later appears wearing a Queen of Diamonds costume, which is the symbol that causes Shaw to enter a hypnotic state. She enters immediately after Shaw is shown the symbol by his manipulative mother, saying "I've been watching you through the window." It almost seems like it is not an accident and she knows what she is doing. This is followed by a scene in which Sinatra proposes marriage to Leigh, followed by a scene in which Shaw (Laurence Harvey) and Parrish tell Sinatra that they have just married.
Are both Leigh and Parrish stooges of some form and are their relationships setup with ulterior motives? Probably not--in fact, all of this is probably most easily explained by the "naive" reading that Leigh and Parrish are behaving honestly, if strangely. But the whole backdrop of the movie is that the "Manchurian Candidate" cannot behave honestly. His actions are hardwired and people do strange things to him in order to control his actions. The interactions with Leigh and Parrish ought to be innocent but these various connections and ambiguities create a sense of paranoia.
It is always unclear who can be trusted in this movie, even the women that these men love.