Meanings
colloquial · idiomaticin a bizarre situation that runs contrary to one's expectations
Da waren nur Bekloppte, ich dacht, ich wär im falschen Film.
colloquial · idiomaticdisconnected from reality; having a twisted conception or understanding of the facts
Du bist wohl im falschen Film.You're living in La-La Land. (translation matches only approximately)
Used other than figuratively or idiomatically: see in, falsch, Film.