خطر شدید: یک معمای برادران مخفی هاردی، جلد اول

ATAC BRIEFING FOR AGENTS FRANK AND JOE HARDY MISSION: To find the mastermind behind a possible attack at the Big Air Games. LOCATION: Philadelphia, PA. POTENTIAL VICTIMS: Top extreme athletes in the country. Thousands of spectators. SUSPECTS: There may be a group of extremists working together. There may be just one. Frank and Joe travel to Philadelphia where they intend to prevent an attack on an extreme sports contest called the Big Air Games.