This study attempts to investigate the difficulties and problems that subtitlers may encounter in subtitling colloquial expressions from Arabic into English. To achieve the main objectives of the study, some authentic examples have been obtained from the subtitled film The Dupes and  analyzed linguistically and translationally in order to identify the subtitling inaccuracies, to highlight the subtitling strategies used by the film's subtitler, and to draw other workable subtitling solutions for dealing with colloquialisms or slang language. Analysis isolates three major problems relevant to subtitling Arabic colloquial expressions into English: (1) some colloquialisms,  especially those reflecting religious overtones, have been missubtitled, (2) some colloquialisms have been totally dropped out from subtitling (i.e. zero-subtitling), (3) and in subtitling certain colloquialisms, a considerable subtitling loss has occurred. Finally, to resolve such recalcitrant problems and difficulties, the study, in its concluding part, suggests some other practical subtitling mechanisms, other than the ones that have been adopted by the film's subtitler.