There was a real story of one woman spy of Russia marrying a German army man and then bore him two children and passed crucial army information to Russia in world war 2. Ye such thing happen, even if rarely.
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I am happy to learn you watch movie.
I will now expect lighter questions from you.
Yes, cops gets into fake relationship to reach the professional mission only in the film. If they try same in real life, only God can save them.