Sandy is a beachcomber who scours Barren Sands looking for interesting shells to sell. He is swarthy and unshaven and wears patched clothes and sandals. When confronted by Frank and Joe Hardy for snatching a shell from Callie Shaw he claimed that his only income was from selling what he found. However, when later investigating Sandy, the boys discovered that he drove a car, a red-and-white hardtop, that he couldn't have afforded with his beachcombing money. They discovered that he was actually working for Orrin North collecting notes relating to the activities of the Footprints spy ring in Bayport. Sandy was supposed to take the shells to a drop-off point for North to collect but when one of the deliveries was intercepted by the Hardys, Sandy panicked and went straight to North's house, North Manor. It was this gaffe that confirmed the boys' suspicions that North was involved with the Huellan spies.