An eccentric like all Helmsleys, eleven-year-old Archer escapes his overprotective mother and recruits two friends, Oliver and Adelaide, to help him plan a rescue of his long-lost grandparents, world-famous explorers who disappeared atop an iceberg in the Antarctic.

"Cruz Coronado sets sail for the shores of Iceland and Norway aboard the Explorer Academy ship to continue his studies at sea. But, things take a turn while exploring the icy north, when he embarks on a dangerous mission to uncover the first piece of an important puzzle his mother left behind" --

On an island nation in the Indian Ocean, the explorers venture through a vast underwater world and take part in a friendly robotics competition. But the tides of good fortune change quickly. Suddenly, Team Cousteau jumps into action to rescue a faculty member from the brink of death. Meanwhile, the team follows the Cruz's mother's clues to a magnificent tomb and center of spirituality precariously perched on the side of a cliff. There, Cruz is confronted...

Dora and Boots go to a carnival where they play games in order to win the grand prize.

"Cruz and his fellow recruits tackle challenging missions to dispense life-saving medication to gorillas, thwart pangolin poachers, and capture images of the last known cheetahs in Namibia--all the while discovering that protecting the world's threatened species is a dangerous business. Things turn deadly for Lani, Sailor, Emmett, and Cruz as they search for the fourth piece of Cruz's mom's cipher. Cruz knows it's not going to be easy, but will an...

"Amid assignments that take the Explorer Academy recruits from the iceberg-filled waters of Antarctica to the bone-dry deserts of Argentina, Cruz Coronado is scrambling to complete the last piece of the cipher. With Nebula agents and the elusive explorer spy still out there, his opportunity to recover his mother's world-changing formula is slipping away. But as Cruz has learned from his time aboard Orion, true explorers must never give up. Even after...

Left stranded in the Amazon jungle when their plane crashes on their way back to England from Manaus, Brazil, four children struggle to survive for days until one of them finds a map that leads them to a ruined city and a secret hidden among the vines.

A boy discovers that the pond in his backyard contains a whole world ready to be explored.

"Cruz Coronado grapples with an important secret as the gang heads to China in search of the second-to-last piece of the cipher. Under the watchful eye of a new adviser, life on the ship returns to almost normal ... Almost. Just as things seem to be going smoothly, a familiar face shocks Cruz back into reality, and the final piece in this life-and-death scavenger hunt veers toward a dead end"--

In this book without words, a boy opens a door and invites the reader to explore the magical world on the other side.