On topic, I agree that they are taking The Proposal idea but like Laila said, The Proposal was not an original movie by itself. There have been many shows even in US and in other countries which have used this storyline. Some have copied it far more than QH has.
I wouldn't call it Plagiarism because QH has only taken the small idea of having them pose as a fake couple and get to go under a test, This type of track has been used many times in shows.
The Proposal had more to the story than just that. Now if they had copied even the dialouges and the entire storyline of The Proposal then I would agree.
Plagiarism are movies like Partner which was an obvious rip off of the american movie Hitch, I can give more examples but its 5 am in the morning here, I haven't slept and my brain ain't functioning properly 😆
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