Expedition Unknown

Chasing archaeology's biggest prize -- the lost tomb and treasure of Alexander the Great -- Josh dives Egypt's coast, revealing ruins of Alexander's Royal Quarter. Josh tunnels under modern Alexandria, but a water pump malfunction puts everything at risk.

Spanning Europe and Africa, Josh's chase for Alexander's remains and fortune ramps up. Clues mount in a flooded ruin beneath Alexandria, Egypt. Later, Josh gathers shocking evidence Alexander's body may actually lie in Venice's St. Mark's Cathedral.

Josh chases the fortune stolen by loyalists to Britain's crown during the American Revolution. Jumping into two investigations of the infamous Doan Gang, Josh helps dig up a cache of plundered coins. Later, a cave search pinpoints the turncoats' hideout.

Weeks before the D-Day invasion, Britain's Barracuda bomber took out the largest Nazi warship ever built -- but today, not a single Barracuda exists. Josh joins a one-of-a-kind restoration project and searches for wreckage far above the Arctic Circle.

Josh dives the waters off Tanzania to find a lost city and its fortunes. From the remote outpost of Zanzibar, Josh searches for ancient shipwrecks. Then, joining an expert team, Josh dives into what could be the walls of a lost city that traded riches.