A campaign of fierce explosive blasts terrorizes Swift Enterprises, targeting the family and friends of Tom Swift. To withstand and outwit the vengeful enemy, Tom and his friends Bud Barclay and Chow Winkler seek secret refuge on Spindrift Island, home of another famed scientific adventurer, none other than Rick Brant! On Spindrift Tom tests a remarkable new invention, the amplitensor, in his aquadisk, a multi-mach watercraft of unique design. But...