I was shocked to know that Teen Devian was awarded an “A” Certificate. I have seen the film twice and decided to watch it again before drafting this answer.
There is on obscenity, vulgarity or voilence in the film which are the major reasons for an, “A” Certificate. There can be only one reason and it is the plot.
In Teen Devian, a charming Dev Anand falls in love with the three ladies simultaneously. Sounds strange, but this is the core plot of the movie. Dev Anand is not fooling them but genuinely likes all three of them for different reasons. Further he visits a hypnotist who takes him in a hypnotized state where he dreams and visualizes his future with each one of them and arrives at a decision. The film released in 1965 and the plot was way ahead of its time. A man falling in love with three ladies at a time can be the reason why it might have received an “A” Certificate.
Personally, I also feel that it's very important how you put up your point in front of the Censor Board. Guide released in the same year and it had a sub plot of an extra marital affair.
It was the time when woman would choose to stay in a bad marriage rather than leave her husband not only in films but also in real life. Still Guide was awarded an “U” Certificate. Therefore it becomes necessary how you convey your point to the Censor Board.
Whatever the reason, Teen Devian is a must watch film with great performances and good music. Though it is a black and white film, the hypnotized dream portion is shot in colour which is the crux of the film (some versions today have the portion in black and white). Just to add on, the film also had an English version but the print was never released. It was titled, “Oh Boys and Three Girls.”
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