During Mr.
Frank and Joe take up the case despite fore warnings..
Strange occurrences at the park also frighten the visitors and animals.
Problems arise for the park owner as he receives pressure from a competitor and a real-estate firm to sell out.
The young detectives look into a clue that takes them into a new animal park outside Bayport, where they are lured into a trap by an unknown enemy.
Hardy\'s investigation of a ruthless gang of terrorists, Frank and Joe witness an explosion in the sky near an airborne dirigible owned by Quinn Air Fleet.
During Mr