Crime in the Cards — Franklin W. Dixon

CREATURE CARDS ARE HOT,
EXPENSIVE -- AND BANNED
FROM BAYPORT HIGH!
Gaming has already caused too much hassling among the students. But the Hardys' friend Chet is really upset when his confiscated deck is stolen from a teacher's locked desk. It's the latest in a string of thefts, and the big tournament is coming up. The police are stumped, but Frank and Joe are playing their best hand to catch the thief.
From a waterfront park to a deserted nighttime mall, the boys uncover a web of Internet action, trading, selling, secret games, and cheating. They're onto a criminal scheme that nets giant profits -- and the decks are stacked against them. But the Hardys have one special trick up their sleeves!