- "A long-lost brother is always a mystery."
- — Tag-line, from front cover
Double Exposure is the 22nd book in The Hardy Boys Casefiles series. It was first published by Archway Paperbacks (an imprint of Simon & Schuster) in December 1988.
When Frank and Joe decide to meet their father's latest contact on their own, they get more than they bargained for. The young detectives come face-to-face with their long-lost brother, Chris Hardy! But a hail of bullets cuts their meeting short.
Suddenly Frank and Joe find themselves trapped in a deadly cross fire between a brutal gang of spies and a high-tech computer scam. Odds are their new brother is the trigger man -- aiming to wipe out an old family debt.