Sarah continues her research on the volcano; Nate and Tomas work through a challenge together; Mike climbs a giant wind turbine.

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 attempts to scale an active volcano in order to land her dream job

A rookie diver struggles underwater to rig a sunken yacht; a heavy haul trucker tries to transport a crane through a hurricane; a tree man fells a large, dead Eucalyptus tree.

Hoping for a job as a commercial diver, Erik welds a patch on a sunken submarine; Rookie heavy haul driver, Fred, battles through Hurricane Patricia; 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; Amateur pilot, Ron, gets his first taste of canyon flying.

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 novice flyer travels to Africa to be take a rigorous bush pilot course.