Volcanologist Sarah continues her first expedition on an active volcano. Rookie tree men, Nate and Tomas, face off in their most difficult challenge yet. And greenhorn wi ...

Rookie tree man Tomas freezes in fear halfway up a redwood. Greenhorn diver Erik descends deep into the ocean to collect research samples. And rookie volcanologist Sarah ...

Rookie diver Erik struggles underwater while rigging a sunken yacht. Heavy Haul trucker, Fred attempts to transport a 105-ton crane through a hurricane. And tree man, Nat ...

Hoping for a job as a commercial diver, Erik welds a patch on a sunken submarine. Three lessons into his bush pilot training, Ron ends up in a hospital. ...

A rookie tree climber jeopardizes his team when he ignores expert advice about scaling a redwood. Dan and Erik attempt a dangerous underwater welding job in San Diego. Am ...

Rookie caver, Kevin, leads an expedition into the depths of a Tennessee cave. Three hopeful rookies compete for a high-flying position with the Sonoma Marin Tree Men. A n ...