"Twelve-year-old twins Bickford and Rebecca Kidd and their two older siblings travel to Africa to track down priceless artifacts that will keep the family's treasure hunting business afloat long enough to rescue their kidnapped mother--and possibly find their missing father"--
"Following clues left by their missing father, twelve-year-old twins Bickford and Rebecca Kidd sail from the Caribbean to New York City with their siblings to finish the dangerous quest of their world-famous treasure-hunting parents"--Provided by publisher.
Bick, Beck, Storm, and Tommy have one week to traverse the Australian Outback, locate Charlotte Badger and her pirate cronies, and find evidence to prove their parents innocent of stealing rare opals.
When they uncover a conspiracy against America and its fundamental freedoms, the Kidd children, accompanied by their great uncle, crisscross the country in a race to prove that a newly-discovered copy of the Bill of Rights is a forgery.