The rule is on a R-rated movie children under 17 must be accompanied with an adult, so even the adult is not going attend the movie with you it might be a good idea for an adult to escort you into theatre to make sure you get in so theatre knows you the adults permission to see the movie. Brendan validates parking so the adult will get parking free, to escort you into the theatre. But if you think that you look old enough (17) it might not even be an issue for you.
Buy your ticket through Fandango. They wont check your ID.
Buy your tickets through fandango
Do not really know
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