What Happened At Midnight by Franklin W. Dixon

After a brazen theft during a midnight blackout at a local party, two teenage detectives pursue the culprit and uncover a jewel-smuggling ring that draws them into chases from Bayport to New York City. Stranded after a pickpocket cleans them out, they resourcefully press on, trace the criminals’ hideouts and methods, and ultimately help bring the gang to justice.

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