At the end of the film, it seems to be very clear that the whole film is a hallucination of herry before his death. As the sperm whale classmate said, this ending cannot give the audience a satisfactory answer, but I really can't think of a more reasonable explanation, because only in dreams can things that seem contrary to common sense in real life happen.
Regarding this film, we might imagine that the director deliberately used Henry's hallucinations to let the audience experience a world where reality and fantasy are intertwined, and in reality to experience what we have only experienced in our dreams. The sudden disappearance, deja vu, staggered identities, etc. all exist reasonably in our dreams, and the same feeling also appeared in the hallucinations of Henry before his death. What appeared in front of us was a fantastic and strange world, and in Henry's life. All this in a dream couldn't be more reasonable.
stay can be understood as henrry's nostalgia for the real world, and it can also be seen as sam's various efforts to save henrry. Henry had always believed that his own driving error had caused the death of a loved one, but this became a reality in a hallucination: he killed his parents with his own hands. He harbors great guilt over the death of his parents, and in his hallucinations his heart brings them back to life in another way, even though he fails to see his mother. Before henrry died, he made a blind old man who looked like his father see the light again, and showed what he hoped to do to his dead parents to make up for the mistake of killing them with his own hands.
The film keeps repeating henrry and sam, the overlapping roles of sam's girlfriend and henrry's girlfriend; the similar ring in sam's hand and henrry's hand after the car accident; sam's hesitation to propose to his girlfriend, and many other details, people can't help but Think: Sam and his girlfriend in the hallucination are likely to be replicas of Henry and his girlfriend in the real world, and Henry is likely to be a psychiatrist in reality and so on. In short, the director has left a lot of imagination space for the audience, and you can weave Henry's real world according to your own wishes, just like the director.
stay well.
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