Ethan and Ella have never been anywhere as cool --- or as old --- as Athens, Greece. Surrounded by crumbling buildings and ancient sculptures, the twins are excited to follow in their Grandpa Harry’s footsteps and explore the ruins. While they’re exploring, they stumble upon a mysterious painting on an underground wall.

While visiting Alaska, the twins see glaciers and grizzlies, kayak through fjords, and learn about polar bears! They also meet some native people who tell them that lately their food supplies have been going missing. And when Ethan and Ella spot some nearby paw prints, they wonder who the paws belong to.

Ethan and Ella are in Australia, home to beautiful beaches and some of the most famous coral reefs in the world --- plus tons of cool fish and other underwater creatures! he twins dive right into the water for some snorkeling at their cousin’s beach house, and while they’re exploring, they come across a watch that’s still ticking. Whose is it?

The Briar family is off to Peru! They explore small towns within the Sacred Valley, go horseback riding up into ancient salt mines, help weave alpaca wool into blankets, and then travel to Machu Picchu, the “Lost City of the Incas.” While Ethan and Ella are exploring the incredible site, they come across a wooden bridge that leads them to a mysterious stone structure. What is it, why haven’t they heard about it --- and why does it seem to look like a snake, a bird, and a puma at the same time?

Ethan and Ella venture into the bustling markets of Mumbai, India, where there are tons of beautiful sights and smells --- from silky fabrics to bread being baked to jars of spices. When one of the spice sellers starts getting complaints about his saffron, he is beside himself. His spices have always been known to be the purest in the market. Ethan and Ella are on the case --- and they soon discover that someone has been meddling with the spices!

Ethan, Ella and their parents travel to the Maasai Mara in Kenya where they stay in a cabin and venture out on safaris every day in search of The Big Five game animals --- the African elephant, the Cape buffalo, the leopard, the rhinoceros and, of course, the lion. The kids are so excited when they see four of the five animals within the first few days, but where are the lions?

From the Great Wall to the dumplings, Ethan and Ella love China so far. And the Forbidden City in Beijing doesn’t leave anything to be desired, either! When the twins get separated from their parents, however, they get do some exploring on their own.

Ethan and Ella are excited to get to Paris --- they’ve only ever seen pictures of the Eiffel Tower! After arriving, the twins receive an email from their beloved Grandpa Harry. He tells them that there’s a secret bakery near the Louvre museum --- so secret, in fact, that you need a password to get inside. Lucky for the twins, their dad wants to take them to see some artwork at the Louvre.

When Ethan and Ella first land in Venice, they are in awe of all the canals and tiny little streets. They’re especially excited to look for a five-hundred-year-old-mosaic near Calle Farnese that Grandpa Harry tells them about. The next morning, the twins hear two gondoliers arguing, one of them accusing the other of stealing his most beautiful boat. The gondolier begs Ethan and Ella to help him find the boat. Will the twins be able to find the stolen gondola?

In the first book of this new chapter book series about mystery, travel, and adventure, twins Ethan and Ella must find a missing coin before they move away from their hometown!