The Hardy Brothers Files is a young adult book series published from 1987-1998. The series has 127 books, including two trilogies, so it is only slightly second only to the original series in terms of length. Unlike other Hardy Brothers book series, which are mostly aimed at children aged 8-12, " Dossiers" were published for a teenage audience. Therefore, these books have a lot more action, but also more violence than Detective Stories. This new atmosphere is evident from the very first chapter of the first book, "His Destination Is Death", in which Joe Hardy's girlfriend, Iola Morton, is killed in a car bombing caused by terrorists.

When Joe's girlfriend is killed in the explosion bomb planted by a terrorist, Frank and Joe Hardy rush to pursue the notorious ruthless terrorist leader, nicknamed Al-Rusasa, who has set his sights on killing a presidential candidate.

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